MALIBU, Calif.—Redmond O'Neal, the son of Farrah Fawcett and Ryan O'Neal, has pleaded guilty in California to possessing heroin and methamphetamine.

The 23-year-old O'Neal pleaded guilty Thursday in a Malibu court to the two felony counts and a misdemeanor count of driving under the influence of drugs. As part of a plea deal, a second DUI charge was dismissed.

O'Neal was arrested Jan. 26 after he was stopped for speeding on Pacific Coast Highway in Malibu.

He was placed on three years probation on the misdemeanor charge and fined about $1,700. He must also remain in drug treatment until a hearing next month.