As stated in the department's Telegram, this became known from the initial testimony of the accused.
“During subsequent interrogations and other investigative activities with their participation... they reported that their actions, both at the preparation stage and after the armed attack in Crocus City Hall, were coordinated through voice messages via the Telegram messenger by a man who introduced himself to them under a pseudonym,” the statement says.
Earlier, the Investigative Committee of Russia stated that during the investigation of the terrorist attack at Crocus City Hall in the Moscow region, it was revealed that the terrorists were connected with Ukrainian nationalists.