BOISE, Idaho (AP) — A Boise man serving two consecutive life sentences for two 2007 murders is now facing charges of assaulting a prison guard.

Ada County sheriff's spokesman Patrick Orr says Todd Hagnas has been charged in connection with an Oct. 30 incident at a prison south of Boise. The Idaho Statesman reports a guard was feeding inmates through an opening in their cell doors when Hagnas complained about a problem with the toilet in his cell.

The officer says Hagnas attacked him moments after he entered the cell. The guard suffered facial injuries. Ada County prosecutors issued an arrest warrant for Hagnas on Jan. 6 on felony assault and battery on certain personnel. Orr says the crime is punishable by up to five years in prison.