MOSCOW, April 6. /TASS/. One of the defendants in the Crocus City Hall terrorist attack case, who had been sentenced to life imprisonment, committed suicide in a pretrial detention center, a law enforcement official told TASS.

Moscow’s Main Directorate of the Federal Penitentiary Service noted that an investigation into the incident is underway.

"On April 6, a prisoner sentenced to life in prison was found unresponsive in a cell at Pretrial Detention Center No. 1 after taking his own life. A medical staff member arrived at the scene immediately and attempted resuscitation, but the efforts were unsuccessful," the statement said.

Earlier media reports identified the individual as Yakubjon Yusufzoda, an accomplice in the Crocus terrorist attack.