OAKLAND (CBS SF) — Police in Oakland deployed a number of tactical teams Thursday morning to serve 16 warrants in at least three counties, making 12 arrests while seizing drugs, cash and a number of firearms, according to Acting Deputy Chief Roland Holmgren.

Holmgren was interviewed, apparently by other Oakland police personnel, in a video released by the department shortly before noon.

“We’re going after an infamous West Oakland gang we believe, and feel very confident, were responsible for terrorizing our community,” Holmgren said.

The suspects have been involved in shootings, robberies and murders in cities as far away as Pittsburg, Antioch, Tracy and Stockton, according to Holmgren.

“They really knew no boundaries when it came to their criminal efforts,” he said.

He added that the law enforcement operations have taken place both within Oakland’s city limits as well as in neighboring cities.

Reports of unspecified police activity have surfaced in Berkeley Thursday morning, involving the closure of northbound Shattuck Avenue near the University of California at Berkeley campus as well as a California Highway Patrol airplane circling overhead before dawn, waking a number of residents who complained on social media.

So far, however, none of those law enforcement agencies have commented on whether their operations this morning are related to one another.

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