CRESAPTOWN, Md. (AP) -- A western Maryland state prison inmate faces a first-degree murder charge in the strangulation of his cellmate.

The Allegany County State's Attorney's Office said Thursday that a grand jury in Cumberland indicted 28-year-old Wesley Curtis for the slaying of 28-year-old Charles Richardson IV at the nearby North Branch Correctional Institution.

Richardson was found in his cell Sept. 27. He had been serving a life sentence for two murders in Columbia in 2007.

Curtis was sentenced to 50 years in 2009 for attempted second-degree murder and a handgun violation in Prince George's County. He had 20 years added to his sentence in 2011 for a first-degree assault in prison.