All four suspects, from Tajikistan, have been remanded in custody until at least 22 May before facing trial, according to Russian authorities.
Three out of four suspects have pleaded guilty after appearing in court charged with terror offences after the concert hall attack near Moscow which killed more than 130 people.
All four suspects, from Tajikistan, have been remanded in custody until at least 22 May before facing trial, according to Russian authorities.
The number of people killed in the attack on the Piknik rock concert at Crocus City Hall Krasnogorsk on Friday night has risen to 137. At least 154 people were injured.
Mirzoyev, Rachabalizoda and Fariduni admitted their guilt after they were charged.
Mirzoyev, a father of four, has been placed in two-month pre-trial detention, which is standard practice in Russia for cases of this nature.
The fourth suspect, Fayzov, was brought to court directly from a hospital in a wheelchair.
Medical staff stayed with Fayzov while he was in court, where he wore a hospital gown and trousers. He appeared to have some cuts.
The other three suspects appeared in court heavily bruised with swollen faces amid reports in Russian media that they were tortured during interrogation by the security services.
Video footage showed them being dragged through the court building before the hearing.