State parole agents and officers from nearly three dozen local agencies participated in "Operation Gangbusters." Most came from the Alameda County Sheriff's Department and Oakland, Hayward, Union City and Fremont police departments.
"It becomes a piece of jewelry that sometimes they forget they're wearing," said Robert Ambroselli, California director of adult parole.
Nearly half of those arrested in the gangster and parolee sweep were wearing state-issued global positioning devices -- a high-tech accessory corrections officials say the parolees wore while committing new crimes.
"GPS plays a big role as an instrument in crime scene correlation for our partners," Ambroselli said. "The data that is extrapolated and then provided to our partners is really where a lot of crimes are solved."
In all, 150 officers from 30 state and local agencies participated in the sweep. The target -- 40 high-risk gang members, but those arrested included a variety of offenders. Of the 48 arrested, 37 were on parole and 11 on probation. Of the total, police say 33 are known gang members.
Among the items seized were 106 marijuana plants from one east Oakland location. Besides the marijuana plants, police seized two guns, two machetes and $5000 in cash.
"The streets are safer today than they were yesterday because of the great work done by our partnership," said Capt. Paul Figueroa with the Oakland Police Department.
Alameda County district attorney Nancy O'Malley promises aggressive prosecution of those arrested.
"We will be taking a look at each individual person who was arrested today to see what evidence there is against them and what charges can be filed against them," she said.
The sweeps are part of a larger effort by the California Department of Corrections to enact the parole reforms signed by Gov. Arnold Schwarzenegger last year. The goal is to place more than 800 of California's known gang members on active GPS monitoring.
"Our message of unity with our law enforcement partners and cooperation to aggressively control gang networking is working," Ambroselli said.
Local agencies expect the sweep to have an immediate impact on crime. In the Laurel District, several of those arrested were from one small neighborhood gang. Others were members of prison gangs, out on parole.