HRABOVE, Ukraine — The chaotic Malaysia Airlines Flight 17 recovery effort stumbled again today, with more bodies found at the sprawling crash site but a worrisome power outage in the refrigerated train holding more than 200 of the dead.

The shambolic attempts to investigate by the pro-Russia separatists who control the farmland where pieces of the plane crashed to Earth have fanned widespread international outrage, especially from the nations whose citizens were on the doomed plane. Four days after the jetliner was shot out of the sky, international investigators still had only limited access to the crash site.

Emergency workers piled 21 more black body bags from the blackened crash site by the side of the road today in Hrabove. That brought the total found to 272 of the 298 passengers and crew killed in the tragedy, according Prime Minister Arseniy Yatsenyuk.

The bodies were being sent to the refrigerated railcars in the nearby town of Torez, where the other bodies are being kept. But a train engineer told The Associated Press that the cars’ refrigeration had been off overnight and it was not immediately clear why. The cooling system was back up and running early today, he said.

The smell of decomposing bodies was much more pronounced today at the Torez train station than a day earlier, when 196 bodies were put into the train cars.

Ukrainian officials say the plane was shot down by a mobile missile battery from a rebel-controlled area in eastern Ukraine. They said the BUK rocket launcher was supplied from Russia and operated by Russian personnel.

The United States presented what it called “powerful” evidence Sunday that the rebels shot down the Boeing 777 with a Russian surface-to-air missile. That evidence included video of a rocket launcher, one surface-to-air missile missing, leaving the likely launch site; imagery showing the firing; phone calls claiming credit for the strike and phone recordings said to reveal a cover-up at the crash site.

“A buildup of extraordinary circumstantial evidence ... it’s powerful here,” said U.S. Secretary of State John Kerry.

“Russia is supporting these separatists. Russia is arming these separatists. Russia is training these separatists,” he added.