PORTLAND, Ore. -- Portland police officers are searching for the people responsible for stealing parts off parked cars in north Portland.

The thieves are stealing catalytic converters and selling them at local scrap metal shops, according to authorities.

One car owner discovered his catalytic converter was gone when he turned his key last week.

"I looked underneath the car and saw there was a missing piece of pipe," the victim said.

Surveillance video shows the thieves stole a converter from a parking lot on Marine Drive in a matter of minutes with other people walking around in the parking lot.

Local buyers offer up to $160 for catalytic converters because there are precious metals like platinum, palladium and rhodium inside.

Some shops are changing rules and requiring identification, but victims say other stores are still turning a blind eye.