A Kenyan man who was convicted of murdering two elderly victims and suspected of killing 22 more in Texas was found dead in his prison cell on Tuesday, officials said.

Billy Chemirmir, 59, was killed by his cellmate, who is also serving a life sentence for murder, at the Coffield Unit in Tennessee Colony, according to the Texas Department of Criminal Justice (TDCJ).

A spokesperson for the Dallas County District Attorney’s Office confirmed Chemirmir’s death to CBS News in Texas.

Chemirmir was accused of posing as a maintenance worker or health care provider to gain access to the homes of his victims, who were mostly women in their 80s and 90s.

He would then smother them with a pillow and steal their jewelry, which he sold for cash.

He was arrested in 2018 after police linked him to the death of 81-year-old Lu Thi Harris in Dallas.

He was sentenced to life in prison without parole in April 2022 after a jury found him guilty of capital murder.

In October 2022, he was also convicted of killing 87-year-old Mary Brooks in Collin County and received another life sentence.

Chemirmir faced 11 more capital murder charges in Collin County and six in Dallas County.

Last month, Collin County District Attorney Greg Willis decided not to pursue the death penalty in those cases.