SoCal police crack down on nitrous oxide sales in auto supply shops LOS ANGELES, March 23 (UPI) -- Three arrests were made in a crackdown on the alleged illegal sale of so-called laughing gas at Southern California auto-racing supply stores, authorities said. A fourth individual was being sought Saturday in the wake of search-warrant executions at 17 businesses tied to the alleged ring. The operation targeted stores in the greater Los Angeles area that allegedly sold nitrous oxide to drug abusers. Racing enthusiasts use the gas to increase speeds, the Los Angeles Times said Saturday. "We want the public, especially parents, to be aware of its abuse by our youth," Los Angeles U.S. Atty. Andreé Birotte said in a written statement. The Times said the 15-month investigation was a response to a spike in traffic accidents involving juveniles under the influence of the gas.