Russia has charged four men it says attacked a Moscow concert hall and killed at least 137 people.
Three were marched bent double into a Moscow court while the fourth was in a wheelchair. All were charged with committing an act of terrorism.
The Islamic State group, or IS, said it carried out Friday's outrage at Crocus City Hall, and posted video.
Russian officials have claimed, without evidence, Ukrainian involvement. Kyiv says the claim is "absurd".
The four were named as Dalerdzhon Mirzoyev, Saidakrami Murodali Rachabalizoda, Shamsidin Fariduni and Muhammadsobir Fayzov, reports BBC.
Video showed three of them being marched by masked police into Basmanny district court in the Russian capital. All appeared injured.
Mirzoyev and Rachabalizoda's eyes were blackened and the latter's ear was heavily bandaged - reportedly from it being partially severed during his arrest.
Mirzoyev also appeared to have a torn plastic bag wrapped around his neck.
Bd-pratidin English/Lutful Hoque
