UKIAH (AP) – Authorities in Northern California have destroyed more than 42,000 marijuana plants as part of an investigation into illegal marijuana farms in public and private land that are impacting the environment.

The Mendocino County Sheriff’s Office said Wednesday that local, state and federal officials last week served 28 search warrants to marijuana farms without a permit along the Eel River in northern Mendocino County.

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The office says the farms visited are suspected of harming the environment by polluting the water with trash, pesticides and generator fuel and damming watersheds.

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Official say sites visited that do not have cannabis permits, state water permits for cannabis or permits from Cal Fire for deforestation and legal tree removal.

It says no arrests have been made but that the cases will be submitted to prosecutors at a later date.

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