The Ukrainian military on Saturday said five soldiers killed during clashes with pro-Russian separatist in the east of Ukraine, marking the highest number of people to be killed in a single day since a ceasefire that was initiated two months ago.
"This is the highest death toll within the past two months. All losses are related to the combat clashes with sabotage groups," Ukrainian military spokesman Andriy Lysenko said.
Lysenko said four soldiers were injured during the clash.
Tensions between the Ukrainian Army and pro-Russian rebels escalated over the past few weeks, after a relatively calm period since early September.
Both sides of the conflict accuse each other of igniting the violence.
The conflict broke out in April 2014 after the Russian annexation of Crimea, as separatists backed by Russia took control of most parts of the Donetsk and Luhansk regions of eastern Ukraine.
At least 8,000 people have been killed in the conflict, while 2 million others have been forced to flee their homes.