According to Alexei Kulemzin, the city’s Russian-installed mayor, Ukrainian forces shelled a busy area where shops and a market are located.

Pushilin said the city was shelled by Ukrainian artillery. There was no immediate comment from Ukraine.

Reuters photographs and video taken at the scene showed crying people, some who said they had lost their relatives, and bodies lying on blood-soaked snow near one of the city’s markets.

Pushilin said emergency services were working at the scene and that forensic specialists were trying to collect fragments of the weapons used in the attack.

Donetsk is one of four Ukrainian regions which Russia claimed to have annexed last year in a move condemned as illegal by most countries at the United Nations General Assembly. Russia does not fully control any of the four regions.