CNN New Day Sunday December 27, 2015 12:27:00
They warn the situation is still potentially dangerous, as they are still many hot spots. new this morning. police across europe are on high alert and have ramped up security measures. they say they have received a warning from a friendly intelligence service that key cities could be attacked between christmas and new year's eve. let's bring in david tafori, a former foreign policy adviser. thanks for being with us, david, this morning. there is always heightened nervousness ahead of new year's eve when it comes to safe places to celebrate. how do you determine if this threat in europe is un...