There wasn't much to celebrate after police arrived early Thursday morning at a Studio City club.
Authorities raided a birthday party at the Platinum Club on Ventura Boulevard. The rental club is just east of Tujunga Avenue.
Investigators said members of the South Los Angeles Rolling 60s gang were at the party. The gang is one of Los Angeles' largest and most dangerous, police said.
"They're one of the larger gangs in South Los Angeles," said LAPD Sgt. Dan Horan. "They're well established. There was a gang injunction against them in the neighborhood that they claim. That area around there is Slauson and Crenshaw in South Los Angeles. They are large in number and notorious in their activity."
The Los Angeles Police Department's 77th Division and North Hollywood officers arrested more than 20 people. Many of the people arrested were on parole, according to authorities.
Police said more people would have been arrested if the computer used to check parole violations had not malfunctioned.
Police blocked off nearby streets during the 2 a.m. operation. About 100 officers were involved.
The club's manager said the operation was a surprise.
"They just busted in the door and told my security to leave," said Michael Scarponi. "They pretty much just took over the club."