Russia branded the deadly shelling of a bus in eastern Ukraine Thursday as a "monstrous" crime and accused Kiev of committing the attack to try to derail peace efforts.

"We are shaken by the monstrous new crime in Donetsk where on the morning of January 22 dozens of peaceful civilians died and received injuries as a result of Ukrainian forces shelling a bus stop," Foreign Minister Sergei Lavrov said in a statement.

He said the attack was a "crude provocation" aimed at undermining peace efforts, noting that the attack came after "tentative progress" reached at a crisis meeting in Berlin on Wednesday.

"It is becoming obvious that human casualties won't stop 'the party of war' in Kiev and its foreign sponsors," Lavrov said, calling for an "urgent" investigation into the incident.

Thirteen civilians died when shells hit the trolleybus in the Kremlin-backed rebel stronghold of Donetsk.

Kiev said ultimate blame rested with Russia, with Ukrainian Prime Minister Arseny Yatsenyuk accusing "Russian terrorists" of launching the attack.

Russia's Investigative Committee, which reports directly to President Vladimir Putin, said it had opened a criminal probe into the shelling.

The committee said it had preliminary evidence showing that the Ukrainian army and the National guard were responsible but that more time was needed to reach a final conclusion.

It said that "no fewer than eight peaceful civilians" died and 12 were wounded.

The Investigative Committee slammed Yatsenyuk for laying the blame at Russia's feet.

"One can congratulate Yatsenyuk and the ministry of propaganda he created," it said in a statement.

"You learnt well the lessons of your teacher Goebbels," it said, referring to Hitler's Nazi propaganda minister.