Russian forces reportedly shelled central parts of the eastern Ukraine city of Kharkiv on Sunday, killing five people and injuring 20.

Videos provided by the Associated Press show emergency workers who had been helping injured people take cover inside a building amid the sounds of a fierce bombardment.

The workers and soldiers then quickly carried the injured to ambulances immediately after the shelling stops.

Kharkiv Mayor Igor Terekhov posted a video message on social media Sunday, urging the city's residents to evacuate and stating that volunteers would help them.

He said that city officials are helping people move to less dangerous places because there are no longer any safe locations in Kharkiv.

He added that officials are providing accommodations, hot food, showers and medical help.