OAKLAND (CBS SF) — A total of seven known violent criminal offenders were arrested Thursday by nine law enforcement agencies that partnered in an ongoing effort to reduce gang violence in Alameda and Contra Costa counties, Oakland police said.

Officers with the Oakland Police Department served 10 search warrants in Oakland, Hayward, Fremont and Antioch as part of Operation Ceasefire, according to Oakland police.

Police recovered evidence during the searches and arrested seven suspects, police said. The suspects’ names have not yet been released.

Oakland police Chief Sean Whent said the operation, which targets offenders who are “associated with gangs and are responsible for homicides, shootings and robberies,” is his top strategy for reducing violence in the city.

San Leandro, Fremont, Alameda and Hayward police participated, as well as Alameda and Contra Costa county sheriff’s deputies, U.S. Marshals and FBI agents.

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