By Andrea Nakano

NOVATO (KPIX) — Catalytic converter thefts have been on the rise and the crime spree is spreading into Marin County. Police have put residents on alert.

Officers say the thieves work in teams going around mainly at night. Typically, one person gets out of the getaway car with an electric saw, gets underneath the car and within minutes leaves the scene with the catalytic converter in hand.

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The trend has seen a huge spike just in the last couple of years.

“Last year we had 94 catalytic converter thefts in Novato, this year we are already at 35 and we haven’t fully made it out of February yet,” said Sgt. Jennifer Dunlap with the Novato Police Department.

The thieves have their eyes on specific cars such as the Toyota Prius.

“They’re mainly going after the low emission vehicles,” said Sgt. Dunlap. “There’s high value in precious metals on the catalytic converters and they’re getting money at scrap yards for these.”

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It is not just occurring in Marin County. Theft of catalytic converters has been widespread in the Bay Area. Just last week, a high-speed chase across the Bay Bridge turned into a big bust. Police found half a dozen stolen catalytic converters inside the trunk of a BMW, in Oakland.

Normally, though, arrests are hard to make. Police say this particular crime is challenging to investigate.

“It is difficult because it just takes a few minutes and they’re gone,” says Dunlap.

It’s a costly crime for victims, who have to pay roughly $2000 to $3000 to get one replaced.

“Clearly people are struggling and they have to rob to get by,” says Petaluma resident Jill Farnsworth.

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The reason why this crime is on the rise is that according to today’s spot prices, some of the precious metals inside are worth more than the price of gold.