It's thought a passenger plane which crashed in Ukraine, close to the Russian border, was shot down.
The Malaysia Airlines jet had 295 people on board.
There are reports of dozens of bodies scattered around the wreckage - which is thought to be spread over 9 miles.
Ukraine's President says his military didn't take action against any airborne targets.
But pro-Russian separatists are blaming the Ukrainian government forces.
The Malaysian prime minister says he's launching immediate investigation.
