ALAMEDA COUNTY, Calif. (KGO) -- In what Alameda County Sheriff's Office is calling the largest pot bust in Bay Area history, more than 37 tons of plants, tens of millions of dollars in product have been seized in multiple raids that span four East Bay cities. So far, at least seven people have been arrested.
Inside one San Leandro warehouse, there were so many marijuana plants in so many rooms, deputies had to take a chainsaw to cut them all down.
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The San Leandro facility is just one of 18 similar warehouses, also in Oakland, Hayward and Castro Valley, busted by Alameda County Sheriffs in recent days.
"We've also seized close to $10 million in cash assets," said Sgt. Ray Kelly with the Alameda County Sheriffs Department. "We've also seized 12,000 pounds of processed product ready to be distributed out into the community. That's worth somewhere in the neighborhood of $40 million."
Authorities believe there are as many as a half-million plants in all, over 500,000-square feet of warehouse space hosting everything from mature three footers to tiny starters.
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"There's CO2 being pumped into these rooms, HEPA filters, filtering the air going out so you're not getting the massive odor," explained Kelly.
The entire operation is supported by an intricate infrastructure, air filters, illegal wiring, generators, water and fertilizers that are toxic, spilling into local drainage.
"They're basically circumventing the legalized system to be involved in the cannabis industry, and they're doing that strictly for profit," said Kelly.
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The marijuana is being grown illegally is untaxed and unregulated, but authorities believe it's actually ending up on the legal retail market, which is being sold at local dispensaries.
The seven people arrested so far face a host of state and federal charges, including drug, weapons, money laundering, and tax evasion. Investigators believe the group has overseas connections.
More arrests are expected.