Russia pummelled towns and villages in Ukraine’s northeastern Kharkiv region on Monday, days after launching a surprise ground offensive over the border that has forced thousands to evacuate.

The Ukrainian army acknowledged Russia was “achieving tactical success” after launching a ground assault on Friday that has sparked the evacuation of almost 6,000 people.

But President Volodymyr Zelensky stressed Ukraine had sent in reinforcements, and that a “counterattack” was ongoing.

“Our task is clear: to thwart Russia’s attempt to expand the war,” he said in an evening address.

Russia’s defence ministry said its troops had “improved the tactical position and dealt a blow to (Ukrainian) manpower” around border villages, including Lyptsi, and the town of Vovchansk.

Kateryna Stepanova, 74, who fled Lyptsi with her son, said several bombs had hit her street.

“We weren’t going to leave… but now this. Thankfully, we’re alive,” she said, sitting in a minibus at a gathering point for evacuees.