VANCOUVER, Wash. (AP) -- Police who searched a Vancouver, Wash., home say they've recovered six suitcases and numerous other items believed stolen from Portland International Airport since last May.

Port of Portland police and Vancouver police say they've identified a group of people believed responsible for 15 instances of baggage theft. The Columbian reports that police don't believe the case is linked to an instance of baggage theft last weekend at the airport.

Of four people detained during Tuesday's search, two were released and two were arrested on unrelated warrants.

Port of Portland spokesman Steve Johnson says police have identified the owners of the stolen property and are in the process of notifying them.

Police say the investigation continues.