A Galveston County Jail inmate is accused of killing another person in custody on Wednesday, according to the Galveston County Sheriff’s Office.

Crystal Walker, 39, was charged with murder in the death of 58-year-old Bessie Burgan, who was assaulted and later pronounced dead after being transported to the University of Texas Medical Branch. Walker was in jail for allegedly violating her probation on a drug charge —possession of a controlled substance in Penalty Group 1 >=1g<4g, according to the sheriff’s office.

Walker’s bond was set at $500,000, authorities said.

The Galveston County Sheriff’s Office and Texas Rangers were conducting separate investigations, and the Galveston County District Attorney’s Office also responded to help investigate, according to law enforcement.

County court records did not appear to show the murder charge early Thursday morning. A defense attorney representing Walker in the drug possession case did not immediately return a request for comment.

Burgan was also in jail on a drug possession charge after a court revoked her probation earlier this year, court documents show. She had failed to pay necessary fees, perform enough community service and attend required appointments.

Her defense attorney’s firm did not immediately return a request for comment.

This is a developing story.