PETALUMA (KCBS)— Petaluma police are warning truck owners to be on the lookout for thieves targeting big trucks’ catalytic converters.

People steal catalytic converters for the recyclable metal, which brings in about $150, but for the truck owners, the cost to replace it can run up to $4,000.

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According to police, most of the thefts have occurred in the Westridge subdivision and on surface streets near the Highway 101/Washington Boulevard off ramp.

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All of the thefts involve pickup trucks including; Dodge diesels, Toyota Tundras and Sequoias.  Police Lt. Ken Savano said they’ve had at least 17 converters stolen in the last week.

“Just be vigilant for any suspicious activity in your neighborhood, any vehicles seen in the area that aren’t from the area; to give us a call and let us contact them and find out what they’re up to,” Savano said.

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Police said they’re looking for suspicious activity like someone using an electric saw, which is how the thief or thieves have been cutting out the converters from underneath the cab at night in these residential areas.