SAN FRANCISCO (KGO) -- New cell phone videos taken by car owners and bystanders illustrate the bold act of stealing catalytic converters in the Bay Area.
It comes as at least one local law enforcement agency made a large catalytic converter theft ring bust.
One cell phone video shows a man holding a hand saw as a woman, who is recording the incident yells, "Excuse me...hey! I'm recording your car and I'm recording you and I'm calling the cops."
The woman who didn't want to be identified says the man was trying to steal a catalytic converter from an old ambulance.
"This is illegal what you're doing!" she yells as the man slinks away in a light blue Lexus SUV.
Meantime in Union City, a woman who also doesn't want to be identified, captured video of a man jacking up a woman's car in a parking lot, shimmy underneath and tossing a catalytic converter to another guy in a sedan. The sedan has no license plate.
"I thought it wouldn't happen at work in broad daylight," says Castro Valley resident Mary Liu who owns a 2004 Honda which was targeted as well, outside her workplace in Alameda.
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In her case, security guards intervened before the job was done.
"You'll see the converter hanging from the car," she exclaims as she points to a wire dangling from the bottom of the vehicle.
The problem now is so widespread insurance company State Farm estimates thefts are up 175% in a 12 month period during the pandemic.
Livermore and Pleasanton Police even formed a task force that recently busted a catalytic converter ring, identifying 30 suspects and recovering more than 50 parts, cash and weapons.
So why are these so valuable to thieves?
ABC7 News went to Downtown Muffler in Hayward to find the answer.
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The owner, Jack Nicholson says he replaces more than two dozen stolen catalytic converters a week.
"Just all of a sudden, WHAM, last year and a half, two years...it's an epidemic," says Nicholson.
He says a few years ago there was a small spike in thefts but nothing like what he's seeing now.
Nicholson has been in the muffler business for 25 years and explained the part "cleans the exhaust system" and "takes the poison out of the exhaust." He went on to explain that it is illegal not to have one in a vehicle in California.
Semi-precious metals such as palladium embedded inside the converter are what thieves are after.
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"They're stealing them for the recycle value of the units," Nicholson says.
He says the parts are often then melted down and the valuable metals extracted.
The cost to a driver? Sometimes as much as the price of the car, as older models are the ones most targeted. Nicholson says he sees Hondas and Toyotas and Priuses. Often the model years are 2002-2008.
It can cost "from $2,000 to $2,500 to $4,000 depending on what area you're shopping in" to have a catalytic converter replaced, according to Nicholson.
Propped up against a wall was a metal plate which Downtown Muffler has been installing more of these days. They cost a few hunded dollars can deter thieves by blocking the catalytic converter.
As we left Nicholson's shop, we met one man who is considering one of these metal plates, after his car was hit days earlier in what he describes a safe neighborhood.
"I can't believe it. In front of my house! It's crazy!
Union City Police say they're looking into the parking lot incident and will respond to our request for information in the coming days.