Sources in US confirm ISIS claimed responsibility for Crocus City Hall attack

The Islamic State group has claimed responsibility for the attack on the Crocus City Hall in a statement posted on affiliated channels on social media, Report informs via CBS.

In a statement posted by its Aamaq news agency, the group said it attacked a large gathering of Christians in the city of Krasnogorsk on the outskirts of the Russian capital of Moscow, killing and wounding hundreds. It was not immediately possible to verify the authenticity of the claim.

A US official tells CBS News the US has intelligence confirming the Islamic State's claims of responsibility, and that they have no reason to doubt those claims. The US official also confirmed that the US provided intelligence to Russia about a potential attack under the intelligence community's Duty to Warn requirement.

National Security Council spokesperson Adrienne Watson confirmed that in a statement provided to CBS News Friday evening.

"Earlier this month, the US government had information about a planned terrorist attack in Moscow —potentially targeting large gatherings, to include concerts— which prompted the State Department to issue a public advisory to Americans in Russia," Watson said. "The US government also shared this information with Russian authorities in accordance with its longstanding 'duty to warn' policy."

A US law enforcement official tells CBS News that there is no known threat to the US emanating from the Moscow attack.

Russia's Federal Security Service, the main domestic security and counter-terrorism agency, said 70 people were killed and more than 100 were wounded in the attack at Crocus City Hall, a large music hall on Moscow's western edge.

The assailants threw explosives, triggering the massive blaze at the hall, which can accommodate 6,000, according to Russian news outlets. Video from outside showed the building on fire, with a huge cloud of smoke rising through the night sky. The street was lit up by the blinking blue lights of dozens of firetrucks, ambulances and other emergency vehicles.

The attack took place as crowds gathered for a performance by the famous Russian rock band Picnic. Russian news reports said concertgoers were being evacuated, but that an unknown number could have been trapped by the blaze.

The prosecutor's office said several men in combat fatigues entered the concert hall and fired on concertgoers.