ISIS has claimed responsibility for an attack at a popular concert venue complex near Moscow Friday after assailants stormed the venue with guns and incendiary devices, killing at least 60 people and injuring 145.

The terror group took responsibility for the attack in a short statement published by ISIS-affiliated news agency Amaq on Telegram on Friday. It did not provide evidence to support the claim.

Video footage from the Crocus City Hall shows the vast complex, which is home to both the music hall and a shopping center, on fire with smoke billowing into the air.

State-run RIA Novosti reported the armed individuals “opened fire with automatic weapons” and “threw a grenade or an incendiary bomb, which started a fire.”

They then “allegedly fled in a white Renault car,” the news agency said.

State media Russia 24 reported the roof on the venue has partially collapsed.

The fire had been brought largely under control more than six hours later.

“There are still some pockets of fire, but the fire has been mostly eliminated,” Moscow governor Andrey Vorobyov said on Telegram.

The deadliest terror attack on Moscow in decades, Friday’s assault came less than a week after President Vladimir Putin won a stage-managed election by an overwhelming majority to secure another term in office, tightening his grip on the country he has ruled since the turn of the century.

With attention focused on the country’s war with neighboring Ukraine, Putin had trumpeted a message of national security before Russians went to the polls.

The carnage broke out before a concert by the band Picnic, according to Russia 24. The band’s manager told state media that the performers were unharmed.

“Unidentified people in camouflage broke into Crocus City Hall and started shooting before the start of the concert,” the Prosecutor General’s Office said, cited by TASS.

Video footage showed panic as the attack unfolded, with crowds of people huddling together, screaming and ducking behind cushioned seats as gunshots started echoing in the vast hall.

One group sheltering next to a large wall of windows outside the concert venue were forced to break them to escape the gunfire, video obtained by CNN shows.

Footage geolocated by CNN shows an armed individual starting at least one fire inside the venue.

The individual is seen carrying something in their hand and, as they walk off-screen, a bright flash of light from a large flame is seen in the video.

A SWAT team was called to the area and more than 70 ambulance teams and doctors assisted victims.

One hundred and forty-five people have been hospitalized, TASS reported. Sixty people are in a “serious condition.”

According to the Kremlin, Putin was informed about the attack and is being kept updated on measures on the ground.

The president on Saturday wished those injured in the attack a speedy recovery, the state-run RIA-Novosti news agency said. He also “conveyed his gratitude to the doctors,” RIA added.

Around 100 people were evacuated from the building by firefighters, TASS reported. Rescuers are still working to get people off the roof, according to the Ministry of Emergency Situations.

Moscow Mayor Sergei Sobyanin called the attack a “terrible tragedy.”

“My condolences to the loved ones of the victims. I gave orders to provide all necessary assistance to everyone who suffered during the incident,” Sobyanin said in a statement.