KYIV, Ukraine — A Russian rocket struck an apartment building in eastern Ukraine’s Chasiv Yar killing at least 15 people. Officials said that more than 20 people could still be trapped under the rubble.

The latest attack on civilian structures was the Saturday night rocket attack. A Russian missile struck a Kremenchuk shopping center in June, killing at least 19 people. In addition, 21 people were killed in rocket fire that hit an apartment building in southern Odesa.

Russia repeatedly claims that it only hits targets of military importance in the war. At a briefing by the Russian Defense Ministry on Sunday, there was no mention of Chasiv Yar.

Pavlo Kyrylenko (the governor of Donetsk, which includes Chasiv Yar), stated that the Uragan rockets struck a town of approximately 12,000 people. These rockets are fired from truck-borne systems.

Later, the Ukrainian emergency services stated that the death toll had increased to 15, and that approximately two dozen people were still living under the rubble. It said that rescuers had spoken to at least three people who were trapped under the rubble.

Chasiv Yar lies approximately 20 km (12 miles) southwest of Kramatorsk. This city is likely to be a major target for Russian forces as they move westward.

The Donetsk is one of the two provinces that together with Luhansk make up the Donbas, where separatist rebels have been fighting Ukrainian forces since 2014. Russia took Lysychansk last week, which was the last stronghold of Ukrainian resistance within Luhansk.

Russian forces are causing “true hell” within the Donbas despite their operational pause, Serhiy Haidai, Luhansk Governor, said Saturday.

Some analysts believed that Moscow’s troops would need some time to regroup and rearm after the capture of Lysychansk.

The enemy has not yet announced an operational pause. Haidai stated that he is still bombarding and shelling our lands at the same intensity as before. Later, he stated that the Russian bombardment in Luhansk was stopped because Ukrainian forces destroyed the ammunition depots and barracks used Russians.