The sweep is focusing on about 200 parolees in cities including Oakland, Berkeley, Hayward and San Leandro, said Fredrick Bridgewater, a spokesman for the California Department of Corrections and Rehabilitation, Division of Adult Parole Operations.
"Periodically we do multi-agency compliance sweeps and checks to make sure that parolees are abiding by their conditions of parole," Bridgewater said.
He said about 180 local, state and federal law enforcement officers from a number of agencies are participating. The officers were briefed at 5 a.m. and began arriving at parolees' homes at 6 a.m.
Bridgewater said the officers are looking for any violations including drugs, guns and gang paraphernalia. In addition, he said, the agents want to "make sure they're residing where they say they're residing."
"If they are found in violation of their parole, they will be taken into custody, which is quite often," he said.
As of 8:30 a.m. the sweep was still under way.