RCMP have laid a murder charge in connection with the killing of an inmate at Stony Mountain prison.

Duane Edward Taylor, 53, was found unresponsive in his cell around 10:15 p.m. on Saturday, Aug. 16, 2014.

Staff members performed CPR, and called emergency services. The inmate could not be resuscitated, said RCMP.

Taylor was serving a sentence for first-degree murder since September 8, 1982.

A source tells CTV News that Taylor had been stabbed, and was in the mental health section of Stony Mountain Institution.

Representatives from Stony Mountain Institution said they take all inmate deaths seriously.

On Aug. 17, RCMP charged Cordell Charles, 25, with first-degree murder.