SAN DIEGO (CNS) - San Diego police Wednesday were investigating a head-on car crash in which Griffin O'Neal, son of actor Ryan O'Neal, was injured in northeastern San Diego.

The 46-year-old O'Neal, who has appeared in several B movies, was the sole occupant of a car that veered into oncoming traffic and struck a van on San Pasqual Valley Road, near Safari Park, about 1 p.m. Tuesday, according to San Diego police.

Paramedics took O'Neal to Palomar Medical Center in Escondido, where he was treated for moderate injuries and released. The driver of the van suffered minor injuries.

Alcohol or drugs are possible factors in the accident, police said.

O'Neal, whose sister is actress Tatum O'Neal, was found guilty of reckless boating and sentenced to community service for a 1986 accident that killed Gian-Carlo Coppola, son of film director Francis Ford Coppola.