The Ukrainian military has said that Russian-backed separatists violated a cease-fire several times overnight.
The headquarters of the Anti-Terrorist Operation, as Kyiv calls the military operation againt rebels who hold parts of the Donetsk and Luhansk provinces, said that separatist forces fired on government positions 16 times between 8 p.m. and 6 a.m., mostly from mortars and grenade launchers.
It said most of the attacks were launched in the Donetsk region, where the rebels fired at Avdiyivka and several other towns.
Separatists in the Luhansk region, meanwhile, said that a railroad bridge linking rebel-held territory with government-held territory had been blown up.
Fighting has eased substantially since the leaders of France and Germany brokered a deal on a cease-fire and steps toward peace in Minsk on February 12, rasing hopes for an end to the conflict that has killed more than 6,000 people since April.
But Ukraine has expressed concern the rebels may be using the cease-fire to regroup for possible new attacks.
With reporting by RIA Novosti and UNIAN