The leader of Russia’s Wagner mercenary group claimed the capture of the eastern Ukrainian town of Soledar early Wednesday, with heavy fighting ongoing in the salt-mining town near the city of Bakhmut.Ukraine denies Wagner founder Yevgeny Prigozhin’s statement and it was impossible to independently verify either side’s claim.If confirmed, the capture of Soledar would mark Russia’s biggest success in its war on Ukraine following months of retreats elsewhere.“Wagner units took control of the entire territory of Soledar… No units other than Wagner PMC fighters were involved in the storming of Soledar,” Prigozhin said in an audio message published by his Concord firm.Prigozhin said the center of Soledar, 15 kilometers from war-battered Bakhmut, was a “cauldron” of urban fighting.He added that the number of captives would be announced later Wednesday.A photo posted by Concord's Telegram channel showed Prigozhin posing alongside Wagner troops inside what is identified as a salt mine in Soledar.

Russian state media reported that Wagner took over Soledar’s salt mines after “fierce fighting.”Prigozhin is an ally of Russian President Vladimir Putin who has been hit with Western sanctions.

His public profile has risen in recent months, openly criticizing some of the Russian military’s top brass over setbacks in Ukraine.The U.S.-based Institute for the Study of War think tank said Tuesday that Prigozhin aims to use claims of Wagner’s successes in Soledar to boost its reputation as an effective fighting force in contrast with the Russian army. The capture of Soledar is a key objective for the Russian military in its larger campaign to take control of Bakhmut, where Russia and Ukraine have faced off in intense fighting for months while suffering heavy losses.The Kremlin however said it was important not to "rush" to declare victory in Soledar, hours after Prigozhin's claim."Let's not rush.

Let's wait for official announcements," Kremlin spokesman Dmitry Peskov said, adding that there was a "positive dynamic in advances" in Soledar and saluted the "heroism of our fighters.""Tactical successes, of course, are very important," he added.Russia’s military meanwhile said that its airborne troops have blocked Soledar from the north and south, while warplanes are striking Ukrainian strongholds and assault forces are engaged in urban fighting.Ukrainian military officials said Kyiv's army hasn't yet surrendered control of the town."Soledar was, is and will be Ukrainian," the strategic communications branch of the Ukrainian military said in a statement, saying pictures released by the Wagner fighting group that Russian media said were taken in Soledar had been taken elsewhere.President Volodymyr Zelensky said there was a "difficult situation" in the Donetsk region in his daily night address on Tuesday.

He praised the "bravery" of Ukrainian soldiers defending Soledar.Ukraine’s Defense Ministry this week called the storming of Soledar “masochistic.”“The enemy disregards the heavy losses of its personnel and continues to storm actively,” Reuters quoted Deputy Defense Minister Hanna Maliar as saying Tuesday.

“The approaches to our positions are simply strewn with the bodies of dead enemy fighters.”AFP contributed reporting.