A car stripped of its catalytic converter. View Full Caption flickr/John And Christina

JEFFERSON PARK — A hunk of precious metal bolted to the underside of most cars is drawing unwanted attention from thieves throughout the Far Northwest Side.

Police warned residents Tuesday that "numerous" cars in the Jefferson Park Police District were stripped of their catalytic converters, which are part of the car's emissions control and exhaust system.

Catalytic converters are prized for the precious metals they contain and the relative ease of taking them off a car, which can be accomplished in about a minute.

Thieves can resell the parts for as much as $1,000, depending on the make and model of the car. But replacing the part can be almost twice as expensive, with some repair shops charging as much as $2,000, police said.

Metal recycling shops are required by law to only accept catalytic converters with proper documentation from the car's owners, police said.

Residents should park in a well-lit area, lock their cars and set their car alarm to be triggered with the slightest motion, police said.

Police also recommended that car owners have a mechanic bolt the converter to the vehicle's frame with a piece of hardened steel welded to the frame of the car and consider installing a separate catalytic converter theft deterrent system.

In addition, residents should watch for people working under cars and call 911 when they see something suspicious, according to the alert. Residents should also watch for vans or trucks double parked on a street with the engine running and record the license plate number of any suspicious vehicle.

Anyone with information about the theft should call detectives at 312-744-8261.

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