MOSCOW (AP) — Russian officials on Saturday accused “the special services of an unfriendly state” of planning and organizing last year's attack on the Moscow concert hall in which 145 people died.

The aim, according to a statement by Svetlana Petrenko, the representative of the Russian Investigative Committee, was to "destabilize the situation in Russia.”

Though she did not specify the “unfriendly state,” she noted that “six Central Asians” currently outside of Russia had been charged in absentia and placed on Russia’s wanted list for allegedly recruiting and organizing the training of four of the suspected perpetrators.

The four suspects, all of whom were identified in the media as citizens of Tajikistan, appeared in a Moscow court at the end of March last year on terrorism charges and showed signs of severe beatings. One appeared to be barely conscious during the hearing.

The attack on Moscow’s Crocus City Hall on March 22, 2024, was the worst in Russia for years. Hundreds of people were wounded.

According to Petrenko, 19 people are currently in custody in Russia in relation to the attack.

A faction of the Islamic State group has claimed responsibility for the massacre in which gunmen shot people who were waiting for a show by a popular rock band and then set the building on fire. But Russian officials including President Vladimir Putin have persistently claimed, without presenting evidence, that Ukraine had a role in the attack. Kyiv has vehemently denied any involvement.

A memorial to the victims of the attack at was unveiled Saturday outside Crocus City Hall, where members of the public came to lay flowers, teddy bears and candles on the first anniversary.