College student Kiley Higgens noticed her Hyundai Santa Fe making a strange noise after she parked the car overnight on the street while housesitting in Phoenix.

“I turn it off and start it again and it still has this super funky weird noise,” Higgens says. “It sounds like it has no muffler.”

Around the same time, a few miles away, Greg Nelson and his girlfriend woke up on a Sunday morning to the same problem with their Toyota Prius.

“It’s very high, boom, boom boom, boom, just like a motorcycle, though I’d equate it to a Harley Davidson,” Nelson says. “If you’ve ever been around a car without a catalytic converter, it’s pretty obvious once you start thinking about it.”

In both cases, a thief snuck underneath the vehicle and stole the catalytic converter. Most cars have them to control the exhaust. And recently, officials have seen a dramatic uptick in thefts of the devices.

In 2018, the New York City Police Department said 200 catalytic converters were reported stolen. Last year, the number spiked to nearly 4,000.

David Glawe of the National Insurance Crime Bureau says the thefts accelerated during the COVID-19 pandemic because of the rare precious metals inside catalytic converters.

“Investors, during times of crisis, gravitate towards investing in these,” he says. “So the price for these precious metals to be stolen or extrapolated out of the catalytic converters is very valuable.”

Stealing a catalytic converter is easy: Thieves slide under the car and slice through the exhaust system using a battery-powered saw in 30 seconds to a minute, Glawe says. They then sell the part to a scrap metal yard for between $150 to $300. Then, the scrap metal yard sells the catalytic converter to another party that removes the precious metals and recycles them into different parts.

“The price per ounce has just gone up exponentially since COVID-19,” Glawe says, “so it’s very valuable throughout that entire supply chain.”

Catalytic converters contain rhodium platinum and palladium, which are primarily produced in Russia and South Africa. Supply chains in the two countries have been disrupted because of sanctions involving Russia and COVID-19 in South Africa.

To prevent theft, some mechanics are painting catalytic converters orange to make them more conspicuous or putting cages around the devices.

The National Insurance Crime Bureau is sponsoring programs to etch vehicle identification numbers on the parts and to add club-like devices to cars to make stealing catalytic converters more difficult, Glawe says.

“Park your car in a well-lit area. If you have a parking garage, put it in a parking garage. Engage with the local crime prevention programs,” he adds. “It’s a holistic approach.”

States including Arizona have legislation pending to address catalytic converter theft. And the National Insurance Crime Bureau is working with Indiana Rep. Jim Baird on drafting federal legislation, Glawe says.

“This is a property crime with a very little deterrent effect,” he says, “but it’s affecting the public and the communities at large tremendously.”

Devan Schwartz produced and edited this interview for broadcast with Tinku Ray. Allison Hagan adapted it for the web.

This article was originally published on WBUR.org.

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