A Montgomery County man has been charged with murder after investigators say he strangled his cellmate inside the George W. Hill Correctional Facility.

Shad Boccella, 25, of Bridgeport, told detectives he killed Elliot Funkhouser in self-defense during an encounter inside the Delaware County jail, according to the affidavit of probable cause for his arrest. Boccella, who was incarcerated for identity theft and receiving stolen property, was arraigned late Tuesday on first- and third-degree murder charges.

Funkhouser, 54, of Rosemont, was awaiting trial on burglary and related charges after being arraigned earlier this month, according to court records.

Sources at the jail who spoke on the condition of anonymity because they were not authorized to discuss the investigation said the two men were housed in a unit for prisoners with mental health issues who require close observation. Boccella was supposed to be alone in a cell because of his involvement in earlier violent incidents, the sources said. But because of a shortage of cells, they said, Funkhouser was assigned to the same cell as Boccella after being transferred from another unit.

County officials disputed that and said in a statement Thursday that there was no shortage of cells at the jail and that the sources’ “unauthorized information” about Boccella was inaccurate.

Warden Laura Williams said through a county spokesperson that prison officials are cooperating with an investigation by the Delaware County District Attorney’s Office and could not comment further because the inquiry was ongoing.

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Corrections officers at the jail — which recently returned to county management after decades of oversight by a private corporation — found Funkhouser facedown and unresponsive in his cell early last Friday, the affidavit said.

He was cold to the touch and had been wrapped tightly in his bedsheets, with a “noose type sheet” on his chest, but not around his neck, the document said. The officer who found him noticed a red mark around Funkhouser’s neck and blood coming from his mouth, according to the affidavit. And one of the sheets, detectives said, was knotted and covered in blood.

Boccella told investigators Funkhouser “came at” him and he had to defend himself, the affidavit said. Afterward, he said, he wrapped him in the sheets.

Funkhouser’s death was the third in three months at George W. Hill, according to county records. An inmate was found hanging in his cell in February and was taken off life support days later at a nearby hospital. In March, another inmate was found unresponsive in his cell, having suffered an apparent medical emergency. He was pronounced dead at the scene, and his death remains under investigation.

On April 6, George W. Hill returned to county control after being managed by the GEO Corp. for nearly three decades. County Council members had fought to regain control of the prison for years and appointed Williams, who previously held leadership positions at the Allegheny County Jail, to run the facility.