Fierce fighting was raging on Saturday for control of several Ukrainian villages near the Russian border as the Russian military sought to press home its attacks in the northeastern Kharkiv region.
Kharkiv's governor said.
"As of now, the enemy keeps pressing in the north of our region. Our forces have repelled nine attacks," Oleh Syniehubov told a media briefing.
Russia's defence ministry said its forces had taken five border villages in the Kharkiv region.
However, Syniehubov said clashes were ongoing in all five villages within a three-to-five kilometres zone from the Russian border.
Ukrainian military said reinforcements were sent to the region to help stabilise positions and limit Russia's advances after it launched its new offensive on Friday.
Syniehubov said regional authorities had evacuated more than 2,500 people from the frontier area, and that process continued.
Top Ukrainian officials have repeatedly said they do not believe Russia has the capacity to launch a successful operation to capture the city of Kharkiv, home to 1.3 million people.
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