A convicted murderer housed at the U.S. penitentiary in Atwater is facing the death penalty for the alleged murder of his cellmate.

A federal grand jury returned a two-count indictment today charging Samuel Stone, 32, with first degree murder and murder by a federal prisoner serving a life sentence.

The indictment alleges that on July 30, 2003, Stone murdered his cellmate, Michael Anita, while the two were being housed in the Special Housing Unit at the Atwater prison.

At the time of the murder, Stone was serving a life sentence for two separate homicides that took place in 1999.

The maximum statutory penalties are life in prison or death. The government has filed a notice of intent to seek the death penalty in this case.