Russian security services report that gunmen have launched an assault on a concert hall located on the outskirts of Moscow, resulting in the death of at least 60 individuals and leaving 100 others wounded.

At least four attackers clad in camouflage gear took part in the attack, in the north-west suburb of Krasnogorsk, BBC-verified video shows.

Crocus City Hall was about to host a rock concert when the gunmen burst into the foyer and then the theatre itself.

Much of the building was engulfed by fire and part of the roof collapsed.

Children are said to be among the casualties and the Russian foreign ministry has condemned a “terrorist attack”.

According to an unverified statement online, militant group Islamic State said it was behind the attack.

US officials told CBS, the BBC’s partner service in the US, that it had obtained intelligence that showed IS had wanted to attack Russia. The White House said it had warned Russia earlier this month of plans for a potential attack in Moscow targeting “large gatherings”.

Russia’s National Guard said it had special units working at the scene to hunt down the attackers. Top Russian officials also headed to Krasnogorsk.

Two weeks ago, the US embassy put out a warning to US citizens to avoid large gatherings, saying it was monitoring reports that “extremists have imminent plans to target large gatherings in Moscow”. It updated its advice on Friday evening, urging US citizens to avoid the vicinity of the attack.

More than 6,000 Russians had flocked to the Crocus City Hall retail and concert complex for a concert by rock group Picnic. One witness said the violence erupted minutes before the band were due to come on stage. Picnic’s band members themselves were unharmed.

Russian President Vladimir Putin has not yet directly addressed the nation, but according to one of his deputies has wished those injured a speedy recovery.

A security guard described how the heavily-armed attackers burst into the foyer firing bullets as he and his colleagues were working at the central entrance.

“There were three other security guards and they hid behind an advertising board,” he told Russian telegram channel Baza. “And those attackers passed 10m [30ft] away from us – they started shooting randomly at people on the ground floor.”

Inside the auditorium a woman said she and other visitors rushed towards the stage, as soon as they realised shots were being fired.

“I saw a person in the stalls with a sidearm and there were cracks [of gunfire] going off, I was trying to crawl behind a loudspeaker,” she told Russian TV.

Fire and plumes of smoke rose into the sky and the hall’s facade burst into flames as glass on the top two floors of the building blew out.