CUMBERLAND, Md. (AP) — A convicted double murderer had 20 years added to his sentence Tuesday for stabbing a correctional officer in an attack that prompted a management shake-up at the maximum-security North Branch Correctional Institution near Cumberland.

Richard Crawford, 45, was already serving life plus 30 years for killing his parents in Prince George’s County in 1993 and stabbing an officer at another prison in 2007.