The operation, which began about 4 a.m., targeted more than 160 gang members convicted of felonies, including vandalism and other gang-related crimes.
Authorities seized weapons and drugs, and also took nine children into protective custody, said Steve Whitmore of the sheriff's department.
Involved in the sweep were personnel from the sheriff's Community Oriented Policing Services (COPS) Bureau; U.S. Immigration and Customs Enforcement; California Department of Corrections and Rehabilitation; and county Probation Department.
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Such operations are conducted periodically to check on whether people are complying with the terms of their probation or parole.