WILKES-BARRE, Pa. (AP) - An inmate sentenced to more time behind bars in the slashing of a guard at a northeastern Pennsylvania prison is vowing an appeal.

Forty-two-year-old Joel Perez was sentenced Tuesday in Luzerne County to 11½ to 23 years. As he was leaving, he told a reporter "I gotta appeal this case."Perez was convicted last month of aggravated assault and other counts in the April 2014 attack on the guard at the state prison in Dallas.Authorities said he used a razor blade melted into the handle of a toothbrush to slice the right side of the officer's face.Perez is serving a life sentence for a killing in Lancaster two decades ago. He maintained his innocence and represented himself at trial, saying he was a "fall guy" and a "scapegoat."