LANCASTER (CBSLA) — Four people have been arrested in an operation to crack down on Lancaster-area water thefts for illegal marijuana grows.

A joint operation made up of Lancaster station sheriff’s deputies, the CHP, and the state Department of Fish and Game made the arrests Thursday and 48 vehicles that were being used to transport water, marijuana, or equipment used to cultivate marijuana, were impounded.

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(credit: Los Angeles County Sheriff’s Department)

Authorities say the volume of water theft in east LA County has been putting fire hydrants at risk and could compromise potable drinking water, all to irrigate illegal marijuana grows.

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“These water thieves are using almost any type of vehicle/containers they can to transport the stolen water such as large tanker water trucks, water cubed containers within backs of beds, trailers with water tanks,” sheriff’s officials said in a statement. “It’s common that these vehicles are traveling on public roadways, with drivers who are typically operating the vehicle either out of class for the commercial truck being used, with expired registration or without valid proof of insurance.”

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Authorities say anyone with information about such water thefts can call the Los Angeles County Sheriff’s Department Lancaster Station at (661) 948-8466.