More than 115 police officers and support personnel from about 20 law enforcement agencies, including the task force and the Daly City Police Department, were involved in the undercover sting operation at the event, "etd.POP 2008," which was promoted as an electronic music festival.
Fifty-five adults and three juveniles were arrested on charges of sales of illegal narcotics or possession for sale of illegal narcotics, according to the San Mateo County Narcotics Task Force.
Authorities seized more than 1,000 Ecstasy tablets as well as Ketamine, marijuana, methamphetamine and over $5,000.
The task force reported that patrons at similar events have used "club drugs" such as Ecstasy, GHB, Ketamine and LSD.
Daly City police Capt. Mike Edwards said that that the promoters of the event as well as management of the Cow Palace were notified in advance about the sting operation.
"The Cow Palace and the promoters of these events are all aware of what's going to happen and are all supportive of our efforts," Edwards said.
All those arrested were booked into the San Mateo County jail and were scheduled to be arraigned at 1:30 p.m. today.