Ukraine is now deploying captured Russian tanks to solidify its gains in the northeast amid an ongoing counteroffensive

KYIV, Ukraine — Ukraine is now deploying captured Russian tanks to solidify its gains in the northeast amid an ongoing counteroffensive, a Washington-based think tank said Tuesday, as Kyiv vowed to push further into territories occupied by Moscow.

The Institute for the Study of War, citing a Russian claim, said that Ukraine had been using left-behind Russian T-72 tanks as it tries to push into the Russian-occupied region of Luhansk.

“The initial panic of the counteroffensive led Russian troops to abandon higher-quality equipment in working order, rather than the more damaged equipment left behind by Russian forces retreating from Kyiv in April, further indicating the severity of the Russian rout,” the institute said.

Earlier this month, Ukraine launched its counteroffensive, pushing into territory around its second-largest city of Kharkiv. Videos and photos showed Ukrainian troops seizing tanks, ammunition and other weaponry left behind by Moscow in an apparently chaotic withdrawal.

In the counteroffensive’s wake, Ukrainian officials found hundreds of graves near the once-occupied city of Izium. Yevhenii Yenin, a deputy minister in Ukraine’s Internal Affairs Ministry, told a national telecast that officials exhuming the dead there found bodies “with signs of violent death.”

“There are many of them,” Yenin said. “These are broken ribs and broken heads, men with bound hands, broken jaws and severed genitalia.”

Ukrainian officials also have alleged Russian forces tortured people in occupied areas, including shocking them with radio telephones dating back to the Soviet era. Russia has repeatedly denied abusing or killing prisoners, though Ukrainian officials found mass graves around the city of Bucha after blunting a Russian offensive targeting Kyiv at the start of the war.

Meanwhile, a Ukrainian push continues in the south of the country. The institute, citing the Ukrainian military, said Kyiv had destroyed ammunition depots, two command posts and an electronic warfare system.

Ukraine’s southern military command said early Tuesday its troops sank a Russian barge carrying troops and weapons across the Dnipro River near the Russian-occupied city of Nova Kakhovka. It offered no other details on the sinking of the barge in Ukraine’s Russian-occupied Kherson region, which has been a major target as part of Kyiv’s ongoing counteroffensive in the country.

— The website of a prominent Russian mercenary group apparently was targeted by hackers. The Wagner Group’s website couldn’t be reached Tuesday morning. Late Monday, the IT Army of Ukraine, a group of hackers supporting Kyiv, posted a screenshot apparently showing the website had been replaced with images of dead Russian soldiers.

— Moscow has likely moved its Kilo-class submarines from their station on the Crimean Peninsula to southern Russia over fears about them being struck by long-range Ukrainian fire, the British military said Tuesday. In a daily intelligence briefing, the British Defense Ministry said those submarines had “almost certainly” been moved to Krasnodar Krai in mainland Russia, instead of a naval base at Sevastopol on the Crimean Peninsula.

“This is highly likely due to the recent change in the local security threat level in the face of increased Ukrainian long-range strike capability,” the British said. “In the last two months, the fleet headquarters and its main naval aviation airfield have been attacked.”