Terror group Islamic State took responsibility for the incident.

Russian Federal Security Service (FSB) chief Alexander Bortnikov has informed Russian President Vladimir Putin about the incident.

"FSB Director Bortnikov reported to Putin on the detention of 11 people, all four terrorists directly involved in carrying out the attack," the Kremlin said as quoted by Sputnik news agency.

This was one of the deadliest attacks in Russia in decades.

Video footage circulating on social media showed the vast complex of the concert hall was on fire following the incident.

Law enforcement officials rushed to the spot after the terror incident unfolded.

The attack occurred ahead of a performance by the Soviet-era rock group "Picnic" at the the Crocus City Hall.

The director of the show told Sputnik news agency none of the band members were injured in the incident.

115 people hospitalised

A total of 115 people, including five children, have been hospitalised following the attack, Russian Health Minister Mikhail Murashko said.

“As of now, 115 people have been injured in the terrorist attack, we have hospitalised them, five of them are children, one child is in serious condition, of 110 adults, 60 patients are in serious condition,” Murashko said on the Rossiya 24 TV channel as quoted by Sputnik.

According to reports, about a hundred people were evacuated from the basement of the structure.

US shared information

A White House National Security Council spokesperson claimed in a statement to Sputnik that the United States recently shared information with Russian authorities regarding a planned terrorist attack against Russia in accordance with its so-called duty to warn policy.