of ukraine. but now new fighting has broken out in the nearby donetsk area and many rebels have left the crash site to join in those battles. secretary of state of the united states john kerry says there's no shortage of evidence showing the crash is the work of pro russian rebels. and he's calling for what he says is a moment of truth for russia. president obama also spoke on the situation in ukraine a little while ago on the south lawn of the white house. building on what secretary kerry said, the president called out the rebels and how they've handled this crash site. >> russianbacked separatists who control the area continue to block the investigation. they've repeatedly prevented international investigators from gaining full access to the wreckage. as investigators approached, they fired their weapons into the area. these separatists are removing evidence from the crash site. all of which begs the question, what exactly are they trying to