Gregory Powell, who kidnapped two Los Angeles Police officers and killed one of them, has died at a prison medical facility in Vacaville.

Powell, 79, fatally shot Officer Ian Campbell on March 9, 1963, after he and Jimmy Lee Smith kidnapped Campbell and Officer Karl Hettinger at a Hollywood intersection. Powell and Smith drove the officers to a Kern County onion field, where Powell shot Officer Campbell in the face.

Powell was convicted and given the death penalty, which was overturned in 1972. The case became the subject of a Joseph Wambaugh book in 1973 and 1979 movie in which actor James Woods played Powell.

Powell was denied parole at least 12 times, including most recently in January 2010 and again in October 2011.

"Gregory Powell was a cold-blooded murderer who avoided the death penalty, but he won't escape God's judgement," said Tyler Izen, president of the Los Angeles Police Protective League in a statement. "While Officer Ian Campbell can never be brought back, nor the damage and heartache caused by Powell and Smith be undone, justice was upheld when the parole board denied Powell’s request for compassionate release and ensured he drew his last breath while confined behind prison bars."

On Friday, Los Angeles city officials honored Officer Campbell by renaming the intersection at Carlos and Gower streets in Hollywood, which will now be known as Ian Campbell Square.

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'Onion Field' Cop Killer Denied Parole