Four suspects have appeared in court in Moscow charged over the terrorist attack on the Crocus City concert hall on Friday that left 137 people dead.

The men were officially identified as citizens of Tajikistan, the Tass state news agency said, and were remanded in custody for two months at Sunday’s hearing.

The court released a video showing police officers bringing one of the suspects into the courtroom in handcuffs, as well as photographs of the same man sitting in a glass cage for defendants. One of the suspects was led blindfolded into the courtroom. When his blindfold was removed, a black eye was visible. Another suspect was brought into the courtroom in a wheelchair.

The men, identified as Saidakrami Murodali Rachabalizoda, Dalerdzhon Barotovich Mirzoyev, Shamsidin Fariduni and Muhammadsobir Fayzov, face charges of a “terror attack committed by a group of individuals resulting in a person’s death”, according to the Tass news agency. All four pleaded guilty.

Earlier on Sunday, Islamic State had released new footage of the attack, corroborating the terror group’s claim to have masterminded the slaughter even as Russia has sought to place the blame on Ukraine, which Kyiv denies.

The incident near Moscow is the deadliest IS-claimed assault on European soil and the deadliest attack by any group in Russia since the 2004 Beslan siege.