CUMBERLAND, Md. (AP) — A convicted murderer faces more prison time for strangling his cellmate at the North Branch Correctional Institution near Cumberland.

The Cumberland Times-News reports that an Allegany County jury convicted Brian Cotter, 25, of second-degree murder in the death of Lewis Thompson Jr.

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The verdict came last Tuesday.

Investigators say Cotter strangled Lewis at the state prison in December 2011. They say he then staged the scene to make it look like the 57-year-old victim had committed suicide.

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Cotter is already serving a life sentence for the 2007 first-degree murder of fellow Dundalk resident Raymond Zubrowski.

Thompson was serving a 40-year sentence for rape.

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