20K marijuana plants seized, 24 arrested in raids of illegal East Bay cannabis operations

HAYWARD, Calif. (KGO) -- State authorities seized more than 20,000 plants and detained two dozen people Thursday following a series of raids on illegal cannabis operations in Hayward.

The California Department of Fish and Wildlife led the operation, targeting three industrial warehouses south of the Hayward Executive Airport.

While officials have not confirmed if the three locations were linked, the task force recovered a total of 20,133 plants and detained 24 individuals.

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State representatives reported finding illegal pesticides with foreign labels at all three sites.

The raid marks the department's second major bust in the city in less than six months.

It follows a year of significant enforcement in Alameda County. In 2025, authorities destroyed 81,377 pounds of illegal cannabis in the county, trailing only Los Angeles in total plant count. The street value of the destroyed plants reached $134 million, the highest in California.

Eric Farb, a cannabis industry expert known as Stinje, says illegal grow locations are a huge problem, and often times dangerous.

"Some of these bigger operations they are using PGR's and recycled water," Farb said. "Some of them are stuffing too many lights in a room and there is mold and mildew on the weed and for the consumer it's actually bad for their health."

Neighbors near the warehouses reported a strong odor of cannabis prior to the raids.

Farb noted that while the legal cannabis industry faces heavy taxes and regulation, illegal shortcuts create an uneven playing field and safety hazards.

"They should have to follow the same regulations that we do, you know?" Farb said. "There shouldn't be any shortcuts, and People's health is at risk here."

Authorities stated the investigation is ongoing and have not released the identities of those behind the operations. Officials emphasized that such "illicit activities undermine California's regulated cannabis market and pose serious risks to public health and the environment."