Law enforcement authorities descended on two Santa Rosa auto businesses Monday as part of an investigation into alleged mishandling of toxic substances, including engine fluids and fuels.

The day-long search operation targeted Cream's Dismantling and Scrap on Copperhill Lane off Airport Boulevard and Cream's Towing on Santa Rosa Avenue. Authorities also searched the Larkfield home of Joseph Cream Jr., 47, who owns both businesses.

The coordinated effort between seven local and state law enforcement and environmental agencies began about 9:30 a.m. and involved search warrants being served at all three locations.

Santa Rosa police, who are leading the investigation, said they were looking for evidence of illegal disposal and handling of vehicle fluids and other hazardous waste.

Some of the suspected activity could have affected local surface waters, said Santa Rosa Sgt. Mike Lazzarini.

He said the investigation was still in its preliminary stage but declined to say when it started.

On April 21, a manager and an employee at Cream's Dismantling and Scrap were arrested for removing police surveillance cameras mounted on a neighboring business.

Lazzarini confirmed the cameras were part of the investigation. He said no charges have been filed against the manager, James Atwood, 45, of Rohnert Park, and Arthur Pereira, 44, of Santa Rosa.

In 2004, Joseph Cream Jr. and one of his managers, Brian Wallace, were arrested on suspicion of illegally selling and disposing of gasoline siphoned from abandoned vehicles. At the time, the company had contracts with the city of Santa Rosa, Sonoma County and the California Highway Patrol to tow and crush abandoned vehicles.

The city and county promptly cancelled their contracts and the company later settled the case, agreeing to pay $25,000 in restitution for dismissal of the felony charges.

In an earlier case in 2004, the company pleaded no contest to violating state hazardous waste laws and agreed to pay a $10,000 fine. The original charges, including six misdemeanor counts, stemmed from a massive fire at the scrap yard in September 2003 that spread to a neighboring truck yard. It was the third fire in a matter of a few years, prosecutors said at the time.

Cream's Dismantling and Scrap has been in operation since 1977, according to the Better Business Bureau.

Police said the Copperhill Lane site temporarily shut down Monday as authorities conducted the search.

Phone and email messages left for officials at both the dismantling and towing business were not returned Monday.

The other investigating agencies include the Sonoma County Sheriff's and District Attorney's offices, the county Water Agency and Fire Department, the state Department of Toxic Substance Control and Department of Fish and Game.