More than 70 Ukrainian soldiers were killed after Russian artillery hit a military base in Okhtyrka, a city between Kharkiv and Kyiv.
Dmytro Zhyvytskyy posted photographs of the charred shell of a four-story building and rescuers searching rubble.
In a later Facebook post, he said many Russian soldiers and some local residents also were killed during the fighting on Sunday.
The report could not immediately be confirmed, the Associated Press reported.
Ukraine’s ambassador to the U.S. told senators her country needs more military weapons as it fights the Russian invasion.
