An underage girl, considered to be a sexually exploited child, was rescued, Sheriff Alex Villanueva said at a Tuesday morning news conference.
According to authorities, 38 of those taken into custody were juveniles and six weapons were recovered.
State alert warns Southern Californians to stay home as hospitalizations set new records in L.A.
Villanueva said his department had received information that the gathering was planned at a vacant home. Such parties often include weapons, illegal drugs and violence, the sheriff said.
Villanueva defended the department's decision not to stop the party after learning it would happen, and said if they had, the girl would not have been rescued.
LASD's Elizabeth Espinosa, however, confirmed a report by the L.A. Times that said sheriff's officials were "unaware" the girl would be there and that she was found by "chance."
Investigators said the Palmdale event violated multiple laws and Gov. Newsom's stay-home order, prompted by the recent surge in COVID-19 cases statewide.
Authorities would have targeted the event under any circumstances due to the alleged drug use, weapons, prostitution and presence of minors, Villanueva said. He added that the gathering highlighted a dangerous underground network of parties that have long been held across the country - well before the coronavirus pandemic.
As health officials tighten restrictions to curb the spread of COVID-19, law enforcement warns underground parties are ongoing "superspreader" events across Southern California.
Authorities say these massive parties are not uncommon even through the pandemic.
Local law enforcement officials say they're getting tips of other party houses along with illegal nightclubs that are operating despite public health warnings about the "superspreader" events.
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