Four private investment groups--Wilshire West Partners, AIA Investments Corp., Amakasu Investment American Inc. and Amakasu Investment Ltd.--are defendants in the criminal proceedings, says Patricia Bilgin, a city prosecutor. They are owners of the 168-unit Wilshire Renaissance Apartments on South Masselin Avenue, not far from a museum that includes the ancient La Brea Tar Pits.

The spill occurred a year ago. The city says it started at the apartment complex, where sump pumps that are supposed to collect naturally occurring oil and tar that ooze from the La Brea Tar Pits failed because they were improperly maintained. The suit says about 285 gallons of crude oil spilled into storm drains, then flowed into the environmentally sensitive Ballona Creek and out to the Pacific Ocean.

The apartment owners have already been fined $345,000 by the Los Angeles Regional Water Quality Control Board. The penalty was the biggest ever levied by the agency.