Three civilians and one Ukrainian soldier have been reported killed over the past day in fighting in the country’s east.
The Interior Ministry said the civilians were killed when pro-Russian rebels fired on the town of Avdiyivka, held by pro-government troops. The town is located north of the rebel stronghold of Donetsk.
The military said the soldier died in the neighboring region of Luhansk.
"The situation has significantly deteriorated in the conflict zone over the past 24 hours," the army said.
Meanwhile, the separatists accused government troops of firing on towns they control.
More than 6,500 people have been killed since fighting between Ukrainian government forces and separatists erupted in April 2014.