The aim of the assault on Crocus City Hall was to destabilize Russia, the Investigative Committee has said

The deadly terrorist attack at the Crocus City Hall concert venue near Moscow was masterminded by the intelligence services of an "unfriendly country," Russia's Investigative Committee has claimed on the anniversary of the attack.

Four gunmen stormed the Crocus City Hall ahead of a rock concert on March 22, 2024, shooting everyone in sight before setting the building on fire. A terrorist organization known as Islamic State-Khorasan (ISIS-K) claimed responsibility for the assault, which took 145 lives and left over 550 injured.

The suspected perpetrators - all citizens of the Central Asian country of Tajikistan - were detained shortly after the attack while fleeing in a car towards the Ukrainian border. More than a dozen of their accomplices have been arrested since then.

"Based on the evidence that has been collected, the investigation concluded that the terrorist act [at the Crocus City Hall] was planned and organized by the special services of an 'unfriendly country' in order to destabilize the situation in Russia," the Investigative Committee's spokeswoman, Svetlana Petrenko, said in a statement on Saturday.

"In order to carry it out, members of an international terrorist organization had been recruited," she added.

Petrenko refrained from naming the exact country that the agency believes responsible for the attack.

Russia compiled a list of 'unfriendly countries' in 2021 and vastly expanded it after the escalation with Ukraine the following year, as a result of which the West backed Kiev. There are currently 49 nations on the list, including the US, UK, Canada, all EU members, Japan, and South Korea.

The terrorist attack was directly organized by six citizens of Central Asian countries, who are currently "abroad, and have been arrested in absentia and placed on the wanted list," Petrenko said.

Those individuals recruited the four gunmen who later stormed the venue. The latter had received training in a foreign country, she explained.

A few days after the attack, the director of Russia's Federal Security Service (FSB) Aleksandr Bortnikov was asked if the US, UK or Ukraine could have been behind it. "We believe that this is the case," he replied.

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Bortnikov later spoke several times about Kiev's involvement in the assault on Crocus City Hall and warned that "the Ukrainian and Western intelligence services are expanding the circle of possible perpetrators, recruited to commit high-profile crimes inside Russia."