Ukrainian forces have liberated the main factory in the town of Vovchansk, four months after its capture in a surprise Russian attack.

Video filmed on soldiers’ helmet cameras showed vicious room-to-room fighting for control of the massive plant that used to make construction supplies.

“Move, move, move,” shouts one Ukrainian commander between bursts of his rifle as he orders his men to storm through a room and up a staircase.

The recapture of the factory is a rare military victory for Ukrainian forces fighting inside Ukraine.

The news late on Tuesday night came just two days before Volodymyr Zelensky is due to meet Joe Biden at the White House to ask for permission to fire US missiles into Russia to shore up the invasion of the Kursk region.

Ukrainian forces had surrounded the factory since the end of May, a fortnight after Russia launched its attack into the Kharkiv region.

Vovchansk lies near the border with Russia and is the biggest town taken in the incursion.

Reports of the battle described how hundreds of Russian soldiers turned the factory into a “fortress”, deliberately creating a “dense” urban combat scenario to ambush Ukrainian soldiers.

Ukrainian’s defence ministry said its special forces had to fight in “hand-to-hand combat” to recapture the factory.

“Despite strong resistance by the Russians, Ukrainian soldiers managed to kill many of them and capture some prisoners of war,” it said.

Photos and video from Vovchansk showed the once lush town of 18,000 people totally destroyed. Its apartment blocks lie in ruins, the roads are ripped up and broken and the trees are reduced to burnt stumps.

Russian military bloggers confirmed the loss of the factory in Vovchansk but they also mocked Ukrainian soldiers for their “pyrrhic” victory.

“The occupied factory buildings will become a magnet for glide bombs,” Rybar told its 1.3 million subscribers.

These are standard bombs retrofitted with fins and a GPS system. Russia has dropped thousands of them across the front line this year.

Further south along the front line in the Donbas region, Russian forces continued to press forward using near-suicidal mass infantry tactics.

On Wednesday, a Russian military blogger published a video of a Russian flag flying from a coal mine in Vuhledar, long considered a Ukrainian bulwark against the Russian advance.

The US-based Institute for the Study of War said that the Russian capture of Vuhledar was imminent.

“How quickly or easily they are able to do so will likely be contingent partially on Ukrainian decision-making,” it said.

Capturing Vuhledar would be the most significant Russian battlefield victory since the capture of Avdiivka in February.

Analysts have said it will add to pressure on Mr Biden to allow Ukraine to fire US missiles at Russia.