Two medieval vases, stolen from an archaeological dig in Bath five years ago, have been returned.
PC Peter Hunt and PC Gemma Kirby turned treasure hunters when one of the Bellarmine vessels, dating from 1650, turned up for sale on eBay.
They worked with the Museum of London Archaeology and tracked down the vessels to a narrowboat in Oxfordshire.
"It was one of the more unusual crimes I've had to investigate," said PC Hunt of Avon and Somerset Police.
"It's a great pleasure to be able to play a part in returning items of Bath's heritage to their rightful owner."
Bellarmine jugs were named after Robert Bellarmine, a saint and cardinal of the Catholic church, and were traditionally used as protection against witchcraft and magic.