Ukrainian troops have regained control of the eastern town of Trostianets, a local official said, potentially marking a significant breakthrough for Ukraine’s counteroffensive that punches a hole in Russia’s effort to encircle Ukrainian cites.

The head of the Sumy regional military administration, Dmytro Zhyvytsky, announced the recapture of Trostianets and another town, Boromlia, in a statement posted on Sunday on Telegram, the messaging app.

If confirmed, the freeing of the towns from Russian control would bring Ukrainian troops within 30 miles of the provincial capital of Sumy, which is surrounded by Russian forces.

The Ukrainian military also announced that its forces had taken control of two towns close to the eastern city of Kharkiv. The gains come after Ukraine announced a series of counterattacks in several regions.

Zhyvytsky said local residents had helped the army defeat the Russian forces.

“Today, our Trostianets and Boromlia were liberated by the armed forces together with local residents,” his statement said. “We bow to the local defence forces and to all those who helped liberate the communities.”

(New York Times News Service)