Marty Boyer's carefully maintained sport utility vehicle growled more like a dragster than a 2001 Honda Passport as he turned the key.

A story from the AP says, he immediately figured out the problem. A half-dozen office colleagues had told him stories about that roar. Their catalytic converters were stolen, too, in a crime rising rapidly across the country, from riverside parking lots in Cincinnati to highways along the California coast.

Stolen converters, which contain small amounts of the precious metals platinum and palladium, follow copper wire and sewer grates on the long list of metal items targeted by thieves who want to cash in on climbing metal commodity prices.

"The second I turned it over, and it sounded like a tank and a Harley, I knew exactly what had occurred," said Boyer, 33, an assistant technology director at a downtown business.

Stories like Boyer's are increasingly common as converter thieves slip under vehicles with battery-powered saws, sometimes in daylight, and in a matter of minutes leave unsuspecting drivers with rumbling exhaust systems and shocking repair bills.