Thefts of catalytic converters are growing across King County.

Kent Police recently recovered nearly 800 catalytic converters, seized about $40,000 in cash and arrested multiple suspects after a lengthy investigation into numerous thefts.

The suspects in custody have been traveling to the King County area from out of state and purchasing stolen catalytic converters from people off the streets, according to a Kent Police statement last week.

As of press time, police had not released details about the arrests.

Thieves have struck vehicles in numerous cities. Federal Way has reported 158 catalytic converter thefts since the start of 2020 — with 80 coming just in the first quarter of 2021. Auburn has had 128 catalytic converter thefts reported since the start of 2020. The King County Sheriff’s Office reports 464 in that same time frame. Kent had just five catalytic converter thefts in 2019, but had 167 in the first five months of 2021.

People steal the converters for the valuable metals inside that they sell to scrap metal dealers. Rhodium, one of the metals in a converter, has skyrocketed to about $28,000 an ounce, though only a small fraction of that quantity — possibly worth $300 — goes inside each converter, according to a npr.org report.

Police noted the average repair cost to replace the converters is $2,000 to $5,000 per vehicle.

More than 4,000 incidents have been reported in the King County area and beyond since January 2020, according to Kent Police.

Detectives waded through stacks of documents, interviewed countless witnesses and processed piles of evidence to make the arrests.

Tips to protect catalytic converters

■ Know if you’re a target — Toyota Priuses, trucks and SUVs, which are easier for thieves to slide under, are popular targets.

■ Secure your vehicle in a locked garage. Set motion-sensitive lights and park in your driveway or in a brightly lit area in front of your home if you don’t have a garage.

■ Install a catalytic converter anti-theft device. Your mechanic or a search of the internet can show you what devices are available, costs and installation requirements.

■ Paint your catalytic converter with a high temperature fluorescent paint and etch your vehicle’s identification number on the painted surface. This makes it traceable and more easily identifiable.

A chart of the number of catalytic converters stolen from cities in 2020 and 2021. COURTESY IMAGE, Kent Police