KYIV: Intense fighting between Russian and Ukrainian forces was taking place around two towns in the Donetsk region of eastern Ukraine, Bakhmut and Soledar, Ukrainian President Volodymyr Zelenskiy said on Sunday.

Fighting has been particularly intense this weekend in the Donetsk and Luhansk regions, which make up the larger industrial Donbas, and the strategically important Kherson province in the south. They constitute three of the four provinces Putin proclaimed as part of Russia last month, moves dismissed by Ukraine and its Western allies as illegitimate.

Bakhmut has been a target of Russia’s armed forces in their slow move through the region since taking the key industrial towns of Lysychansk and Sievierodonetsk in June and July. Soledar is located just north of Bakhmut.

“The key hot spots in Donbas are Soledar and Bakhmut,” Zelenskiy said in his nightly video address. “Very heavy fighting is going on there.”

Russian forces shelled Ukrainian positions on several fronts on Sunday, the General Staff of Ukraine’s Armed Forces said, with the targets including towns in Kharkiv, Donetsk and Kherson regions.

Ukrainian military analyst Oleh Zhdanov suggested the heaviest fighting was occurring north of Bakhmut, asserting that Ukrainian forces had repelled Russian advances on the towns of Torske and Sprine in the past 24 hours.

“(The Russians) have decided to move through Torske and Sprine,” Zhdanov posted online. “Positions in those places are changing hands regularly. Our command is diverting reinforcements there, men and artillery to counter the Russian superiority in those areas.”

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Russia’s defence ministry said on Sunday its forces had repelled efforts by Ukrainian troops to advance in the Donetsk, Kherson and Mykolaiv regions, inflicting what it described as significant losses.

Russia also said it was continuing air strikes on military and energy targets in Ukraine, using long-range precision-guided weapons.

Rybar, a pro-Russian military channel on Telegram, said Ukrainian armed forces again shelled Belgorod, a town in southern Russia that serves as a staging ground for Russian forces.

Anti-aircraft units intercepted most of the attacks, but there were two explosions near the airport. Three people were injured, it said.

Shelling by Ukrainian forces damaged the administration building in the city Donetsk, the capital of the Donetsk region, the head of its Russian-backed administration said on Sunday.

“It was a direct hit, the building is seriously damaged. It is a miracle nobody was killed,” said Alexei Kulemzin, surveying the wreckage, adding that all city services were still working.

There was no immediate reaction from Ukraine to the attack on Donetsk city, which was annexed by Russian-backed separatists in 2014 along with swathes of the Donbas.

Reuters was unable to independently verify the battlefield reports.