A former child actor who was the voice of Charlie Brown in beloved "Peanuts" TV specials has pleaded guilty to making criminal threats.

Fifty-nine-year-old Peter Robbins of Oceanside entered pleas Tuesday. He's facing four years and eight months in prison.

Authorities say Robbins threatened to harm a mobile home park manager and San Diego County Sheriff Bill Gore, offering $50,000 to have Gore killed.

Robbins said the threats stem from his bipolar disorder and paranoid schizophrenia.

Two years ago, Robbins pleaded guilty to threatening a former girlfriend and her plastic surgeon.

From age 9 to 13, Robbins was the voice of Charlie Brown in a series of 1960s animated classics, including "A Charlie Brown Christmas" and "It's the Great Pumpkin, Charlie Brown."