The man who was the voice of Charlie Brown in the first "Peanuts" television specials has pleaded guilty to threatening and stalking both his ex-girlfriend and a plastic surgeon who gave her a breast enhancement he paid for.

City News Service says 56-year-old Peter Robbins entered the plea Wednesday in a San Diego court and could get up to three years in prison at his sentencing next month.

Prosecutors say Robbins called his former girlfriend dozens of times a day and told her he would kill her and her son if she did not give back his dog and car.

They say he made similar threats and demanded a refund from the plastic surgeon.

Robbins provided the voice of the title character in 1965's "A Charlie Brown Christmas" and 1966's "It's the Great Pumpkin, Charlie Brown."