The deadly attack on a concert hall in Moscow in photos

A group of shooters stormed a concert hall on the outskirts of Moscow At least 40 people were killed and more than 100 injured on Friday evening, Russia’s top security service said saidstate news agencies said.

Authorities in Russia have yet to identify who was behind the attack, although U.S. officials said they believe Islamic State was responsible for the attack shortly after the terrorist group took responsibility.

The attack also led to explosions and a massive fire at the venue, Crocus City Hall, one of the largest and most popular concert halls in Moscow and the site of a shopping center.

State media agencies reported there were up to five perpetrators, and the Russian Investigative Committee, the country’s equivalent to the FBI, said it had opened a criminal case into a terrorist act.

Mykhailo Podolyak, a top adviser to the Ukrainian presidential office, said in a video statement that “Ukraine had absolutely nothing to do” with the attack.

On March 7, the US embassy in Moscow issued a decision security alarm warned that its staff was “monitoring reports that extremists have imminent plans to target large gatherings in Moscow, including concerts.”

Below, a body in the parking lot outside the concert hall after the attack.

Firefighters were working to extinguish the fire in the concert hall.

A still image from a video obtained by Reuters shows armed men walking through the concert hall and shooting at people.

Security personnel ordered people outside the concert hall.

A Russian National Guard officer in the parking lot after the attack.

A police officer shouts outside.

A couple walked through the parking lot after the attack.