fighting started in eastern ukraine soon after russia annexed ukraine's crimea peninsula. the un says more than 10,000 people have died in the conflict. andrew plant has the story. in the war—torn east of ukrainian, carried on buses, hundreds of prisoners are headed home, some after years of captivity. more than 300 people, in one of the biggest prisoner swaps since the ukrainian conflict began, the first such swap in september last year, arriving with no belongings, shivering in temperatures close to freezing, but glad to be finally free. translation: i am very happy that i am going back to ukraine, and i thank everyone for the work that has been done to be able to see my loved ones again. translation: i want to believe people are tired of all this. they must find strength to engage in a dialogue, because without that, we will be in a deadlock with no way out. the prisoner transports arrived in the early hours in the east of ukrainian. it happened watched by tight security. ukrainian armed forces on one side, on the other, the russian backed eastern militia. the conflict began more than three years ago soon after russia annexed ukraine's crimea peninsula in 2014. the un estimates more than 10,000 have since died to be the latest on wednesday, a soldier, the first death since christmas when the ceasefire started last saturday. a late present for families and loved ones who have spent many months campaigning to have them set free. but this exchange has been smaller than many hoped for. hundreds more prisoners are still held by both sides. earlier i spoke to a global affairs analyst. he's a former spokesperson for the organisation for security and co—operation in europe — which has a special monitoring mission to ukraine. i asked him how significant the prisoner swap was. it is a very positive development in an otherwise very bleak situation. do not forget, this conflict has gone on forfour years, one of the longest running complex in europe the second world war. even though the christmas ceasefire did not hold for more than a few hours, the exchange showed the two sides could make their guns silent enough for this swap to happen. there are others behind both lines that need to be treated. and also, this is an important component of the minsk agreement, that prisoners are swapped. the most important thing at the end of the day is that the ceasefire takes hold. very important to that donald trump has provided lethal weapons to ukraine, which deepens their involvement. it may strain relations with russia. is it a game—changer? not yet. do not forget, the amount of weapons are limited, a lot of training will be needed to use them, especially for anti—tank weapons. you can see russia is taking this seriously. the attack on the poroshenko administration and donald trump administration took place. but it gives them the ability to secure positions and not let the russian backed separatist take more down the ground. all of this rhetoric coming from russia happens in the context of the elections in russia. president putin needs to show himself, he has not much to show, as a strong man, having the ability to fight and get more territory from russia. there has been a lot of bloodshed in eastern ukraine in recent days. i do not think the christmas ceasefire last that long. is any movement on anything good news? absolutely. the death toll is well over 10,000 now. several million displaced, including some in ukraine. it has been bad. the busy christmas season right now, many people cross the long contact line to visit friends and relatives. that is important. one more thing, all indications are that the rebels are weaponising for more conflict. areal surveillance is detected, believe it or not, aerial military schools the rebels can activate at any time. that indicates to me at least they are willing to use new ways to show the ukrainians, including from the air possibly. an improvised explosive device has gone off in a supermarket in the russian city of st petersburg. local officials say ten people are in hospital — one is in a serious condition. the incident is being investigated as attempted murder but no theories have been ruled out. the bbc‘s tim allman reports. emergency services were quickly on the same. the explosion taking place at around 6:30am local time. a small home—made devices detonating, according to local media, in the lock—up where shoppers leave their belonging. packed with pieces of metal, around 200g belonging. packed with pieces of metal, around 200 g of tnt, it could cause carnage. wonder woman's face was covered in blood, said this eyewitness, and one man was limping. from outside, the damage looked fairly limited. some broken last and shattered windows. there have been injuries but no death. now the authorities are on the hunt for the bomber or bombers. so far it has not been described as a terrorist attack but nothing is ruled out. translation: an investigation is which includes experienced officers from the security service and interior ministry. all possible theories are being worked on. russia and saint petersburg itself is no stranger to bomb attacks like this. in april, 16 people died when the city's metro system was targeted. in the summer, saint petersburg is due to host games in the football world cup stop an incident like this will have the authorities on edge. russia isa have the authorities on edge. russia is a target and whoever carried out this latest attack is still at large. tim allman, bbc news. in syria, aid workers have started to move critically—ill children from a rebel—held suburb near the capital, damascus. after months of negotiation, 4 patients were taken out of ghouta on tuesday night. another 25 are expected to be moved in the coming days, although hundreds more are in urgent need of treatment. around 400,000 people have been under siege by government forces since 2013. from beirut, our correspondent martin patience. seven—year—old imjy is preparing for a shortjourney, and it will almost certainly end up saving her life. she is suffering from haemophilia, but last night she was among four critically—ill patients to be evacuated to damascus for life—saving treatment. this is what she's leaving behind. eastern ghouta is one of the last remaining rebel strongholds, fighting the government of bashar al—assad. it's been bombed and besieged for four years, with fighting intensifying in recent weeks. i think it's a combination of everybody‘s efforts, that at this really low time in syria there is a ray of light, and it's the children. it's the children who are missing growing up in syria — we must sort them out, to give syria a chance of a prosperous and peaceful future. but food is hard to come by. malnutrition is now widespread. human rights groups accuse the syrian government of trying to starve the rebels into submission. this evacuation may have the appearances of a humanitarian gesture, but that's simply not the case. we've been told by two sources that the syrian government only agreed to it as part of a prisoner exchange. the main rebel faction in eastern ghouta agreed to free 29 syrian government hostages, and in return the same number of critically ill patients are being allowed to receive urgent medical care. but the united nations says hundreds of others need to be evacuated. among them, three—month—old karim, who was injured by government shelling. he lost his left eye. his mother was killed. despite a prominent social media campaign, he is not being allowed to leave eastern ghouta. translation: karim is injured, he's going to lose his sight. here in the ghouta he can't get treated. the doctor wants to perform an operation, so that he doesn't lose the sight in his other eye. for some there is now hope, but for most help is not coming any time soon. martin patience, bbc news, beirut. let's take a look at some of the other stories making the news: peru's culture minister has resigned as the controversy continues over the president's decision to pardon the country's former leader, alberto fujimori. it's not clear why the minister, salvador del solar, a former actor and film director, left his post. but he had been under pressure from peruvian artists and opposition leaders, to stand up for human rights. there's been another day of protests in the moroccan city ofjerada following the deaths of two brothers in a disused coal mine. the mine had been closed for years, but the protesters said many young people have no option but to carry on working below ground. they demanded action against unemployment and rising living costs. an arctic cold snap is bringing sub—zero temperatures and heavy snow to large parts of north—east america and canada. temperatures have been reported as low minus fifteen in toronto. while the us lakeside city of erie, in pennsylvania, has had a record 1.5 metres of snow in 48 hours, with more on the way. laura podesta from cbs news reports. residents of 0swego, new york, started digging after three feet of snow fell overnight, forcing officials to declare it a state of emergency. it continued until wednesday. i have lived here my whole life and have not seen it for a few years. we really got hit this year. records were broken in erie, pennsylvania. five feet fell over the past few days. for much of the north—east and mid—west, snow has given way to the bitter cold. in minneapolis, single—digit temperatures froze this minnehaha falls. a bridge in green bay became partially stuck because of the cold. and this is what is called pancake ice in michigan. people are bundled up new york. but that won't stop them from watching the ball drop. how many layers will you were? how many layers will you wear? two pairs of socks, two pairs of nylons, pants, two pairs of socks, a pair of thermals. preparations are under way to make sure the ball drop goes smoothly. authorities say it is built to withstand extreme weather. bbc weather presenter ben rich explained for us why this particular snowstorm has been so severe. north america is used to cold winters but they rarely bite quite as hard as this. temperatures are well below average and some places, particularly on the eastern shores of the great lakes, have seen a huge amounts of snow courtesy of something we call lake—effect snow, it happens when cold winds from the arctic blow across the slightly less cold waters of the great lakes. that slightly less cold moist air rises, it forms clouds which are then blown into the eastern shores of the great lakes and that moisture in the cloud is released not as rain but as huge amounts of snow. over the next few days we can expect more of this because of the cold air that is sitting in place is not going anywhere fast and the winds will still be blowing down across the great lakes picking up that moist and slightly warmer air and delivering it in the form of snow fall across the eastern shores. perhaps not in the huge amounts that we've been seeing over the last few days but any further snow across this part of the world will not be welcomed. snow and ice have also been causing disruption in many parts of the uk, with thousands of homes without power and dangerous conditions on the roads. the runway at stansted airport, north of london, was closed twice on wednesday with a number of flights cancelled. 0ur midlands correspondent phil mackie reports from warwickshire. horn blasts. the motorway at a standstill. it's always busy here anyway, but throw in five centimetres of snow and you've got chaos. 0n the a14 things were even worse. this lorry span out of control, leaving drivers stranded. good morning. it's just gone past 10 o'clock in the morning. as you can see, we're stationary here on the a14, not going anywhere. i've been here for five hours, and... ..so have these! my name is tara, i'm on the a14 trying to go eastbound to northampton. i set off from my house in hinckley at 6am this morning, i've been on the a14 for three hours now. as you can see, there's nothing going in the other direction. i'm a bit cross, i'm canadian so i'm used to this kind of weather. i know you guys aren't. in the end, they were stuck for seven hours before the road was cleared. and it wasn'tjust the roads. stansted airport had to close twice to clear snow from the runway. birmingham airport had to do the same for a short while too. and the weather kept ground crews busy, as planes had to be constantly de—iced. a swathe of central and southern england was worst affected, from gloucestershire, to warwickshire, to the chilterns. and it didn'tjust lead to hazardous driving conditions. thousands of homes lost power, too. obviously the snow came in, it settles on our overhead conductor. then, with the cold wind chill, that freezes into ice and therefore that takes the conductors down. likewise, it's the same with tree branches. normally they would not be near the line but they've taken our conductors down. as the snow started to melt, there was a new danger... flood warnings followed the thaw as streams became swollen and rivers started to rise. that meant more hazards to negotiate, and not everyone made it... it's really been a difficult day. here in warwickshire they've had flooding, snow and power cuts. to get around, you've really needed a specialist vehicle. and tonight, there's another warning as temperatures have fallen, the snow and slush has begun to freeze. phil mackie, bbc news, warwickshire. stay with us on bbc world news, still to come: the harry and barry show — the former president talks to the british royal about the irresponsible use of social media. the most ambitious financial and political change ever attempted has gotten under way with the introduction of the euro. tomorrow in holland we will use money we picked up in belgium today and we will use the same money in france. it has got to be the way to go. george harrison, the former beatle is recovering in hospital after being stabbed at his oxfordshire home. a 33—year—old man from liverpool is being interviewed by police on suspicion of attempted murder. i think it was good. just good? no, fantastic! that's better. this is bbc world news. the latest headlines: the ukrainian government and russian—backed rebels have carried out the biggest prisoner exchange since the conflict began nearly four years ago. syrian volunteers have evacuated the first group of critically—ill children from a rebel—held suburb near damascus. how do you stop poachers devastating wildlife in remote parts of the african continent? one solution — though some people are very uncomfortable with it — is military—style training and tactics now being used in the vulnerable state of chad. zakouma national park has lost 90% of its elephants over the past 40 years. at one point there were fewer than 500 left. the bbc‘s alastair leithead travelled to the park to find the elephant population finally recovering and tourists helping fund conservation. they were the herd heading for extinction. but the elephants of zakouma national park have made a dramatic recovery. translation: before, there used to be elephant carcasses everywhere . so what has been the difference, since african parks took over? translation: since african parks arrived here, we no longer see carcasses of elephants in the park. across the continent, a private, not—for—profit conservation group called african parks believes it has the answer to saving africa's disappearing wildlife. and it's controversial. they are arming rangers and giving them military—style training. in some places, it's become a war against poachers. adoum allam is a sniper with fast response unit mamba number two. his father was killed by poachers in this park. he jumped at the chance to join. "it's a very dangerous job but i love doing it", he said. it's a good income. but it's also personal. this was zakouma, ten years ago. decades of poaching killed 90% of the park's elephants and many rangers as well. but, today, it's a much healthier picture. they haven't lost an elephant in two years or a ranger since 2012. and last year, the population started to grow again. there were more than 20,000 elephants in this parkjust 40 years ago, but now there arejust over 500. what's encouraging, though, is that they've now got babies, they're reproducing, their numbers are starting to go up. and if the poachers can be kept at bay, the population is going to recover. this is the best way to counter raids from the heavily armed sudanese horsemen. the main perpetrators who've been poaching ivory here for centuries. but now, both sides have automatic weapons. and local communities are a key to success. schools are being built, kids are learning about conservation. villagers now often tip off the rangers, if poachers are seen nearby. african parks take on delegated management of protected areas in africa. normally where public sector has failed, african parks will step in and, with donorfunding, will then manage protected areas. but eventually it should pay for itself. zakouma is now attracting high—end adventure tourists who cover one third of the park's budget. 0ther, marginal reserves in africa will never make money. animals have to be worth more alive than dead, notjust to rich westerners, but to local people as well. alastair leithead, bbc news, zakouma national park, in chad. a coach carrying chinese tourists has crashed in iceland. it happened 250 kilometres east of the capital. the occupants of the car escaped unhurt. 0ne chinese national died at the scene and 12 others have been taken to hospital by helicopter. former president barack 0bama has been talking to britain's prince harry about the irresponsible use of social media. in an interview for the bbc mr 0bama said social media is distorting people's understanding of complex issues. he did not mention donald trump by name. but he emphasised that people in positions of leadership should exercise care when posting. 0ur royal correspondent, nicholas witchell has the story: prince harry, first of all. you are very welcome to our studio. good morning. joining the today programme for the day had been a big learning curve, harry said, but he had enjoyed being the interviewer rather than the interviewed. it was quite fun, especially interviewing president 0bama. his principal scoop had been to persuade barack 0bama to give his first interview since standing down as us president. the word "trump" was never mentioned but may have been in mr 0bama's mind when he warned about the use of social media. all of us in leadership have to find ways in which we can recreate a common space on the internet. one of the dangers of the internet is that people can have entirely different realities. they can be just cocooned in the information that reinforces their current biases. harry had also interviewed his father — the main focus had been on climate change. the issue prince charles has championed for decades and for which he was sometimes derided. maybe now, some years later, they are beginning to realise that what i was trying to say may not have been quite as dotty as they thought. i mean, the issue really that has to go on being focused on, big time, i think, is this one around the whole issue of climate change which now, whether we like it or not, is the biggest threat multiplier we face. and then, at the end of the programme, it was time to face questions rather than ask them. first about his fiancee, meghan markle, and herfirst christmas at sandringham. she really enjoyed it. the family loved having her there. and yeah, it's. .. there's always that family part of christmas. there's always that work element as well and i think, you know, together we have an amazing time. great fun, staying with my brother and sister in law. harry's commitment to issues he cares about like the armed forces and mental health had come through strongly. so how does he see his future? part of my role and part of myjob is to shine a spotlight on issues that need that spotlight, whether it's people, whether its causes, whether its issues, whatever it is. so i will continue to play my part in society and do myjob to the best of my ability, so i can wake up in the morning and feel energised, and go to bed hopefully knowing i've done the best that i can. not so long ago, harry admitted to having doubts about a royal role. clearly no longer. nicholas witchell, bbc news. more on that and on all the news at any time on the bbc website. don't forget you can get in touch with me and some of the team on twitter, i'm at bbc mike embley if you are out and about early this thursday morning, bear in mind that conditions could be slippery out there. frost and ice to contend with where we had wintry weather during wednesday and that clears away. then the sky cleared overhead and thursday starts off with the risk of ice. there are still wintry showers exacerbating the risk across some northern and western areas. freezing fog developing across parts of northern ireland as well perhaps, and if that fog develops it could linger through the day. for most of us, thursday is a cracking day. plenty of sparkling winter sunshine. a closer look at three o'clock in the afternoon. despite the sunshine through the midlands, central southern england, temperatures will only reach three degrees, possibly hitting five in london. kent into east anglia, a much drier day with a lot of sunshine. fine for the bulk of northern england. a few showers drifting across north—west england, fading as the day goes on. sunshine across much of scotland butjust a couple of degrees. wintry showers still in the far north. any fog that develops early across northern ireland could stick through to the end of the day. sunny skies for the most part. fine for much of wales and for the bristol area. somerset and dorset into devon. but for cornwall a change. cloud and outbreaks of patchy rain. it will not amount to much as we go on into thursday evening. thursday night will be another cold and frosty one for the majority. the odd fog patch as well. but then things begin to change from the west. rain flooding in from the atlantic, running into that cold air and that could temporarily give snow to northern ireland, wales, the midlands and during friday proper, northern england and southern scotland could see some snow, even to fairly low levels. still a lot to play for with the details on that and we will keep you posted and up—to—date. to the north of the weather system is still cold and to the south is much milder. 10 degrees there in the far south—west. as we go on into the weekend, that mild weather will increasingly make its presence felt. the frontal system bringing rain and perhaps some hill snow in the north through the early part of saturday and then once it leaves we are left with fairly brisk and mild south—westerly wind. some showery rain, spells of sunshine as well. mild in the south but still cold air holding on further north. that mild airedging northwards as we enter sunday. still some showery rain and spells of sunshine as well. that is all from me. bye for now. this is bbc news, the headlines: the ukrainian government and russian—backed rebels have completed one of the biggest prisoner exchanges since the conflict began nearly four years ago. the red cross says more than 230 people have now crossed a checkpoint back to rebel—held territory. the first critically—ill patients have been evacuated from a rebel—held suburb near damascus. a total of 29 are being taken out of eastern ghouta under a deal agreed by syria's government and rebels. aid groups had urged president assad to allow treatment for urgent cases including seven children with cancer. in the us, record—breaking snowfall of more than 150 cm has hit the pennsylvanian city of erie over the christmas period, and more snow‘s expected. forecasters say the extreme weather is caused by very cold air passing over the unfrozen great lakes. now on bbc news, victoria derbyshire takes a look back at the exclusive interviews and films which have featured on her programme in 2017.