Authorities in South Carolina say an inmate accused of slaying a gas station clerk in Edison killed his cellmate during a fight.

News outlets report Marcus Antonio Wright, 23, was charged with murder in the death of Matthew Williams at Lieber Correctional Institute in Dorchester County.

According to an arrest warrant, Wright and Williams were in their cell when they got into a fight.

Authorities say Wright used a "personal weapon" on Williams, causing severe injuries to his face and head.

The warrant says Williams died from blunt force trauma.

Wright was awaiting extradition to New Jersey on murder and armed robbery charges in the 2018 death of John Bertram, 38. Wright is accused of fatally shooting Bertram while robbing the gas station in Edison.

It's unclear when Wright will be extradited.