WASHINGTON — Video of a rocket launcher, one surface-to-air missile missing, leaving the likely launch site. Imagery showing the firing. Calls claiming credit for the strike. Recordings said to reveal a cover-up at the crash site.

“A buildup of extraordinary circumstantial evidence … it’s powerful here,” said Secretary of State John Kerry, a former prosecutor, and it holds Russian-supported rebels in eastern Ukraine responsible for shooting down Malaysia Airlines Flight 17, with the Kremlin complicit in the deaths of nearly 300 passengers and crew members.

“This is the moment of truth for Russia,” said Kerry, leveling some of Washington’s harshest criticism of Moscow since the crisis in Ukraine began.

“Russia is supporting these separatists. Russia is arming these separatists. Russia is training these separatists, and Russia has not yet done the things necessary in order to try to bring them under control,” he said.

In a round of television interviews, Kerry cited a mix of U.S. and Ukrainian intelligence and social media reports that he said “obviously points a very clear finger at the separatists” for firing the missile that brought the plane down, killing nearly 300 passengers and crew.