Emergency workers in eastern Ukraine continued to search for survivors in the ruins of three buildings that were hit in a Russian rocket attack in the eastern town of Chasiv Yar.

At least 18 people were confirmed killed when the residential buildings were struck late on Saturday.

On Sunday, one man was pulled from the rubble after a lengthy operation to free him from under the concrete. He was whisked away to hospital and it was not known if he had sustained any serious injuries. Emergency services said the latest rescue brought to six the number of people dug out of the rubble.

An estimated 24 people were believed still trapped, including a nine-year-old child.

Cranes and excavators worked alongside rescue teams to clear away the ruins of one building, its walls completely shorn off by the impact of the strike.

The rocket assault was the latest in a recent burst of high-casualty attacks on civilian structures.

At least 19 people died when a Russian missile hit a shopping mall in the city of Kremenchuk in late June. Another 21 people were killed when an apartment building and recreation area came under rocket fire in the southern Odesa region this month.

Russia has repeatedly claimed that it is hitting only targets of military value in the war.

There was no comment on Chasiv Yar at a Russian defence ministry briefing on Sunday.

Chasiv Yar is located about 20km (12 miles) southeast of Kramatorsk, a city that is expected to be a major target of Russian forces as they grind westward.