Federal, Local Police Raid House in San Dimas, Discover Huge Drug Lab : Raid: Four people are arrested in what may be the largest and most sophisticated methamphetamine manufacturing operation ever uncovered in California. About 700 pounds of the drug are seized.

More than a dozen federal and local law enforcement officers descended upon a house in a quiet San Dimas neighborhood Wednesday and found what is believed to be the largest and most sophisticated methamphetamine laboratory ever discovered in California.

The four-bedroom house with an attached garage contained at least 700 pounds of the drug in various states of processing and in various forms, including 300 pounds of the clear, potent form known on the street as “ice.” Officials put the street value of the drugs at $31 million.

Three men and a woman who were in the house at the time of the 8 a.m. raid were arrested and several guns were confiscated, authorities said.

Reporters taken on a tour around the outside of the single-story, stucco and brick-facade dwelling could see through windows and a glass sliding door that nearly every room was filled with chemicals and equipment used in processing methamphetamine--including huge glass beakers attached to heating units, large metal drums and pressurized tanks.

The house--which neighbors in the 500 block of East Baseline Road said was rented out by its owner about three months ago--was so contaminated with toxic and hazardous chemicals that officials said it might have to be razed.

The presence of the chemicals could have at any time caused an explosion, said Los Angeles Police Chief Daryl F. Gates, who, along with Sheriff Sherman Block, held an afternoon press conference outside the home as hazardous waste technicians began a massive cleanup effort.

Investigators from the LAPD and the Sheriff’s Department provided information over the last two months that led to the execution of a search warrant Wednesday, the two officials said.

They speculated that a swimming pool in the back yard of the home that was filled with dirty, green water may have been used to dump chemicals.

The lab, they said, was capable of producing about 70 pounds of the drug weekly and probably supplied the entire Western section of the country.

Its operators, the officials said, may have planned to sell the drug to “crack” or rock cocaine users as the supply of cocaine dwindles nationwide.

“The ice clearly can be substituted for rock cocaine,” Gates said, adding that it was unusual for a methamphetamine lab to be set up in a highly populated area. Most such operations, he said, are found in rural or desert areas.

“We have not seen ice in any significant amounts on the streets of Los Angeles, because rock cocaine was readily available,” he said.

Lt. Jim Welch, chief of the LAPD’s clandestine lab unit who took part in the raid, said the four arrests were made without incident.

It appeared, he said, that at least one person was at the house at all times and that several people slept there overnight. Diapers found inside indicated that a child was sometimes kept there. Welch said officers also found records of the drug operation, including “a journal of every batch they cooked up.”

As police technicians dressed in jumpers, gloves and paper shoe covers combed the house, cataloguing and packaging evidence, neighbors stood along the street in small groups, watching.

“We saw people coming and going sometimes, but they didn’t talk to anybody,” said one man, who would not give his name. “We don’t know what kind of people they were. They were very secretive.”

He said he had seen a little girl, about 3 years old, at the house on several occasions.

Sandy Yount, who lives a few doors away, said the only odd thing she had noticed about the raided house was that its lawn was unkempt.

“That’s unusual for this street,” she said.

Other area residents said the home’s owner moved out earlier this year and planned to sell the house, but was renting it in the interim.

Gates and Block said that, under the law, the owner, identified in property records as Davinder S. Sekhon, will have to pay for the cleanup of the chemicals and the razing of the house, if that becomes necessary.

“If you lease your house to someone and they use it for a drug operation, then any loss that results is the responsibility of the owner,” Gates said.

Sekhon could not be reached for comment.

Authorities identified the four people in custody as Carlos Castaneda, 47, Charlie Lopez, 24, Luis Macias, 60, and Deborah Babakitas, 24. They were booked at the sheriff’s Walnut substation on suspicion of manufacturing narcotics.