Nearly 500 people arrested at Southern Calif. EDM festivals

Police in Southern California arrested hundreds of people over the weekend at several electronic dance music festivals, authorities said, as scrutiny mounts on the high-profile events known as raves due to drug-related deaths in recent years.

Police in Pomona, some 30 miles east of Los Angeles, arrested 310 people at the two-day HARD Day of the Dead festival, headlined by popular artists including Deadmau5 and Skrillex.

Most of the arrests were for public intoxication, a police statement said, as well as for being under the influence or in possession of a controlled substance. Dozens more were arrested for carrying fake ID cards.

Police did not report any serious injuries or deaths at the event.

Another 30 miles east of Pomona, authorities in San Bernardino arrested about 180 people at the Escape: Psycho Circus, the Los Angeles Times reported. The newspaper said the charges were similar to those at the Pomona event, and no major incidents occurred there either.

Electronic dance music, known as EDM, has become one of the world's most popular genres as DJs and pop artists collaborate on weekend-long raves, drawing massive crowds that sometimes number hundreds of thousands of revelers.

Over the past years, several people have died due to overdosing on substances including "Molly," the street name for a drug that is pushed as the powder form of a banned substance known as MDMA, the main chemical in ecstasy.

Like ecstasy, Molly can deliver lengthy, euphoric highs with slight hallucinogenic properties that amplify the effects flashing lights and thumping bass, hallmarks of a rave.

A Los Angeles Times investigation found about 20 people who have died due to drug overdoses at raves run by L.A.-area companies nationwide since 2006.