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Ukraine said on Monday it was fighting to keep control of the city of Severodonetsk as Russia deploys its modern Terminator vehicles in a battle for the eastern stronghold.
Regional governor Sergey Gaidai said that while the city remained “completely under the Ukrainian flag”, Russian forces had attacked surrounding villages overnight.
The city is part of the eastern Luhansk breakaway enclave where Russia is trying to capture territory from Ukraine after repositioning forces away from Kyiv towards the Donbas region last month.
Mr Gaidai accused Russia of using “scorched earth tactics” by shelling a city which he said had only one working hospital with three doctors and enough supplies for 10 days.
Ukraine’s human rights commissioner Liudmyla Denisova said the Russian attacks were turning Severodonetsk into a “new Mariupol”, the southern port left in ruins by a weeks-long siege.
Settlements are being shelled with artillery and volley fire, and Russia has “thrown all its forces to storm Severodonetsk,” she said.
Western officials say Russia is trying to expand the territory that Moscow-backed separatists have held since 2014 in the eastern Donbas and connect it along the southern coast to the annexed Crimean peninsula.
Britain’s defence ministry said in a regular intelligence update that Russia had probably deployed its only operational company of BMP-T Terminator tank support vehicles to aid the assault on Severodonetsk.
The Terminators are of post-Soviet design and were developed to prevent heavy tank losses following earlier wars in Afghanistan and Chechnya, British officials said.
They said the presence of the tanks in Severodonetsk suggested that a Russian formation known as the Central Grouping of Forces was involved in the attack after suffering heavy losses in the failed offensive towards Kyiv.
“The Severodonetsk area remains one of Russia’s immediate tactical priorities,” the ministry said. “However, with a maximum of ten Terminators deployed, they are unlikely to have a significant impact on the campaign.”
Mortar shells and missiles also continued to pound Kharkiv in the north, as well as Mykolaiv and Zaporizhzhia in the south, Ukrainian officials said.
At least seven civilians were killed while eight others were wounded in Sunday's bombardment of the Donetsk region, said the Ukrainian army.
Russia said it was preparing to resume its offensive on Slovyansk, a city in the Donetsk breakaway enclave, where fierce fighting was reported last month after Moscow’s troops retreated from Kyiv.
Ukraine’s parliament voted on Sunday to extend martial law and mobilise its armed forces for a third time, until August 23.