FILE - Saidakrami Murodali Rachabalizoda, a suspect in the Crocus City Hall shootings, is escorted by police and FSB officers in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the Moscow concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Dalerdzhon Mirzoyev, a suspect in the Crocus City Hall shootings, sits in a defendants’ cage in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the Moscow concert hall, the bloodiest assault on the Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Saidakrami Murodali Rachabalizoda, a suspect in the Crocus City Hall shooting, sits in a defendants’ cage in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Saidakrami Murodali Rachabalizoda, a suspect in the Crocus City Hall shootings, sits in a defendants’ cage in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the Moscow concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Mukhammadsobir Faizov, a suspect in the Crocus City Hall shootings, sits in a defendants’ cage in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the Moscow concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Russian President Vladimir Putin lights a candle on March 24, 2024, to commemorate victims of a deadly attack two days earlier at the Crocus City Hall. The attack on the concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (Mikhail Metzel, Sputnik, Kremlin Pool Photo via AP, File)
FILE - Rosguardia (Russian National Guard) servicemen secure an area at the Crocus City Hall on the western edge of Moscow, Russia, on March 23, 2024. The attack on the concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (Alexander Avilov/Moscow News Agency via AP, File)
Dmitry Medvedev, deputy head of Russia's Security Council, speaks at a lecture at the 2024 World Youth Festival in Sochi, Russia, Monday, March 4, 2024. Medvedev later declared that if investigators prove Ukraine's involvement in the March 22 concert hall attack in Moscow, Russia should respond by deploying hit men to kill Ukrainian leaders. (Ekaterina Shtukina, Sputnik Pool Photo via AP)
FILE - A couple stand at a makeshift memorial in front of the Crocus City Hall on the western outskirts of Moscow, Russia, on March 26, 2024. The attack on the concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)
FILE - Dalerdzhon Mirzoyev, a suspect in the Crocus City Hall shooting, sits in a defendants’ cage in Basmanny District Court in Moscow, Russia, on March 24, 2024. The attack on the concert hall, the bloodiest assault on Russian soil in two decades, appears to be setting the stage for an increasingly harsh response by President Vladimir Putin. Four suspects in the attack appeared in court showing signs of brutal treatment while in custody. (AP Photo/Alexander Zemlianichenko, File)