Marvin Banks, 29, had been arrested in the fatal shooting of two Mississippi police officers. On Friday night, Banks was found unresponsive in his cell and rushed to a local hospital, where he was pronounced dead.
According to NBC News, "Autopsy results showed Banks died of severe heart disease, but toxicology tests are still pending." He was pronounced dead at 7:40 p.m. local time (8:40 p.m. ET). Forrest County Coroner Butch Benedict told the news station that Banks' body showed no signs of trauma.
Banks was in an "isolation cell" when he was found, NBC reports. The sheriff's department did not release the last time Banks had been checked on by an officer or the last time he'd been seen alive.
Banks, his younger brother Curtis Banks and two other suspects were arrested in the May 9 fatal shooting of Hattiesburg Police Officers Benjamin J. Deen, 34, and Liquori Tate, 25, who had stopped the car that Banks and the others were riding in for speeding, NBC reports.
According to the news station, "[Marvin] Banks, the alleged shooter, was charged with two counts of capital murder, grand theft auto and illegal weapons possession. He was denied bail."
Marvin Banks' cause of death has not been determined, and Mississippi's state medical examiner will conduct the autopsy, NBC reports.
Read more at NBC News.