The leader of a pro-Russian paramilitary group in eastern Ukraine has died in hospital after being injured in an explosion in Moscow on Monday morning, Russian media have said.

Armen Sargsyan, the leader of the “Arbat” battalion, was severely injured following a blast in the entrance hall of a residential building in north-west Moscow, 12km (7 miles) from the Kremlin.

He was evacuated to a hospital by helicopter and placed in intensive care after the explosion, but eventually succumbed to his injuries, according to usually reliable Telegram sources.

Others – including one of Armen Sargsyan’s bodyguards – were also reportedly seriously injured, with some sources saying one other person had died.

In December, the Ukrainian security service SBU said “crime boss” Mr Sargsyan was a suspect in “recruiting prisoners to fight in Ukraine” and added that he had been on an international wanted list since May 2014 for his involvement in murders carried out in the centre of Kyiv.

The SBU added that Mr Sargsyan was part of the inner circle of fugitive former Ukrainian President Viktor Yanukovych.

“The assassination attempt on Sarkisyan was carefully planned and was ordered. Investigators are currently identifying those who ordered the crime,” TASS quoted a law enforcement official as saying.

Images shared on social media show rubble and plaster strewn across a heavily damaged entrance hall with blown-out windows and doorways.

Olga Voronova, a 36-year-old mother of three who lived in the building next door to the explosion, told AFP news agency that she was “very scared” and did not understand how the blast could’ve happened.

“We have quite serious security guards, they ask every car at the checkpoints, we order passes for guests, even for family members,” she said.

Mr Sargsyan was born in Gorlovka, a town in Ukraine’s Donetsk region which has been occupied by Russia since 2014.

In a Telegram post confirming his death, the town’s mayor, Ivan Prikhodko, said Mr Sargsyan’s “most significant achievement was the creation and leadership of a separate special forces battalion”.

Mr Prikhodko said Mr Sargsyan was also the head of the Boxing Federation of the self-proclaimed Donetsk People’s Republic.

The “Arbat” battalion has been known to operate in Russia’s Kursk region, where Ukrainian troops are still present after they launched a surprise offensive in August.

There have been a number of attacks on high profile supporters of Russia’s invasion of Ukraine, in Moscow and in occupied areas.

Senior Russian naval officer Valery Trankovsky and Russian prison boss Sergei Yevsyukov died after car bombs exploded in Russian-occupied Ukraine in late 2024.

And in December, a high-ranking general in the Russian armed forces and his assistant were killed in Moscow by Ukraine’s security service, a Ukrainian source told the BBC.