DALLAS (NewsNation) — A Texas inmate accused of killing 22 older women and one man was slain Tuesday by his cellmate, according to prison officials.

Billy Chemirmir, 50, who was convicted last year in the slayings of two women, was found dead in his cell at a prison in rural East Texas, Texas Department of Criminal Justice spokesperson Hannah Haney said. He was killed by his cellmate who was also serving a prison sentence for murder, according to Haney.

Haney did not release the name of the cellmate, how Chemirmir was killed or what may have led to the slaying.

Chemirmir’s death comes about two weeks after Texas’ 100 prisons were placed on a rare statewide lockdown because of a rise in the number of killings inside the facilities, which prisons officials have said were related to drugs.

The Texas Tribune reports Chermirmir was an inmate at the same unit where another violent incident between inmate and staff occurred the day before the lockdown was announced.

According to The Tribune, the Texas Department of Criminal Justice denied the violent incidents were the reason for the lockdown. The pause was intended to restrict inmate’s movement and allow for intense searches for contraband.

Chemirmir was caught after a 91-year-old woman survived a 2018 attack and told police a man had forced his way into her apartment at an independent living community for seniors, tried to smother her with a pillow and took her jewelry.

Police said they found Chemirmir the following day in the parking lot of his apartment complex holding jewelry and cash, having just thrown away a large red jewelry box.

After Chemirmir’s arrest, police across the area reexamined deaths, and the charges against him grew.

Chemirmir, who maintained his innocence, was serving two sentences of life without the possibility of parole. He was imprisoned at the Coffield Unit in Tennessee Colony, about 100 miles southeast of Dallas.

The Associated Press contributed to this report.