A man convicted of two murders and Austin Caldwellaccused of killing over 20 elderly women was killed by his cellmate Tuesday morning, officials confirmed.

Billy Chemirmir, 50, who was serving a life sentence without parole for the murders, was discovered dead in his cell early in the morning, according to Amanda Hernandez, spokesperson for the Texas Department of Criminal Justice.

His cellmate is also serving a life sentence for murder, Hernandez said in a statement to USA TODAY. The cellmate was not identified and Chemirmir's cause of death wasn't revealed.

Accused of preying on older women, stealing jewelry

Chemirmir was convicted for the murders of 80-year-old Lu Thi Harris and 87-year-old Mary Brooks in 2018. Authorities believe he preyed on older women over a two-year span, and would steal their jewelry. He'd been indicted on 22 capital murder charges in two Texas counties.

He was finally caught when Mary Annis Bartel, who was 91 at the time, survived an attack in March 2018 and told investigators about a man who forced his way into her apartment at an independent living community for seniors, tried to smother her, and stole her jewelry. Bartel died in 2020, but told investigators she knew she was in "grave danger" when she opened her door and saw him.

Police found Chemirmir the next day, holding jewelry and cash, having just thrown away a jewelry box. The contents of that box led investigators to Harris' home, where she was found dead in her bedroom, lipstick smeared on her pillow.

Brooks' daughter, Ann Brooks, said after he was convicted of her mother's death that her family was “thrilled that this defendant will never be able to hurt any other family again.”

Authorities initially ruled Brooks had died of natural causes, but re-evaluated the case after the attack on Bartel. The number of suspected murders committed by Chemirmir grew in the years after his arrest as authorities took closer looks at cases of older women who were thought to have died naturally despite some families pointing out that jewelry was missing.

“Our beloved mother, Mary Sue, her life is over and her jewelry is gone, but her love and her memories will live in us forever,” Ann Brooks said.

Chemirmir had maintained his innocence since his capture and court records show he attempted to appeal his convictions. He was serving out his sentence at the Coffield Unit about 100 miles outside of Dallas, according to prison records.

Contributing: The Associated Press