ISIS claims responsibility for attack in busy Moscow-area concert venue that left at least 60 dead.

ISIS has claimed responsibility for an attack at a popular concert venue complex near Moscow Friday that left at least 60 dead and 145 hospitalized after assailants stormed the venue with guns and incendiary devices.

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

Video footage from the site of the attack, the Crocus City Hall concert venue, 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 attack unfolded before the music group Picnic was set to perform, according to Russia 24. The band’s manager told state media that the performers were unharmed.

The Russia Prosecutor General’s Office said: “Unidentified people in camouflage broke into Crocus City Hall and started shooting before the start of the concert,” according to 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.

Regional governor Andrey Vorobyov said everything was being done to save people in what is now the deadliest terror attack on Moscow in decades. A SWAT team was called to the area and more than 70 ambulance teams and doctors were assisting victims.

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

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

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

On Friday night, Moscow City Duma Chairman Alexey Shaposhnikov called on Moscow residents to donate blood to help treat victims, saying that “this is a matter of life and death for dozens of people.”

Shaposhnikov listed several blood center facilities in the Moscow area that will accept donors throughout the weekend.

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 Main Directorate of the Ministry of Emergency Situations of the Russian Federation.

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

“Today a terrible tragedy occurred in the Crocus City center. 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.

Sobyanin said on Telegram that he was canceling all sports, cultural and other public events in Moscow this weekend.

Shaman, the singer of the band Picnic which was due to play the venue, said he would pay for the funerals of the victims and treatment for those injured.

“We are all one big family. And in a family there is no such thing as somebody else’s grief”, the singer, known for his nationalistic views, said in a video posted on the Russian social media network Vkontakte to his more than 600,000 followers.

“My people, any troubles and misfortunes have always united our country. They have made Russia tougher and stronger. It will not be possible to frighten and break us this time either”, he said.