cal, we are launching immediate investigation." here is what we believe in the early going has happened. with every indication seems to be is that separatist working in the east of ukraine that were pro-russians fired off some sort of missile surface-to-air missile. there are indications that group they were trying to hit another plane. we have recently learned this. and now it appears instead they hit a passenger jet, a boeing 777 with 295 people on board. and we've just gotten word from journalists on the ground there, and i quote "bodies are scattered for miles around the smoking debris seen." so what happened, who is responsible, and what degree this is escalate an already very difficult situation? let's turn to jennifer griffin