At least 39 people were killed and 87 wounded on Friday when two rockets hit a railway station in eastern Ukraine packed with evacuees, Ukrainian authorities said.

Ukrainian President Volodymyr Zelenskyy described Russia as "evil with no limits" after the rocket attack.

"They are cynically destroying the civilian population. This is an evil that has no limits. And if it is not punished, it will never stop," Zelenskyy said in a statement on social media after the strikes.

However, the defense headquarters in Donetsk said the Ukrainian troops launched a Tochka-U missile attack on Kramatorsk and called it a "provocation".

"Ukrainian authorities first announced evacuation from Kramatorsk and Slavyansk, and then performed provocation with a Tochka-U rocket," Donetsk region's commander Eduard Basurin was quoted as saying by Russian media.