Thieves posed as prospective buyers before stealing tens of thousands of pounds worth of fine art from an auction house.
The raiders got away with 43 lots of silverware and Chinese jade sculptures that had been expected to sell for more than £30,000 in total.
They broke into the saleroom the night before the items were due to go under the hammer, after a viewing day.
Police suspect the gang visited the Dominic Winter showroom in South Cerney, Gloucestershire, earlier in the day to check out security and to pick out their intended loot.
Staff at the auction house said items could have been stolen to order – and feared the silverware may already have been melted down.
Missing items include an Edward VII silver table centrepiece, expected to fetch £1500-2000, a Victorian silver teaset with a guide price of £1000-1500, and rare Ming dynasty jade finial, predicted to fetch between £2000-3000.
Buyers from around the world had already put in bids for some of the items.
And now sellers could lose out in their bids for compensation from the auction house’s insurers, as payouts will be based on the catalogue’s guide price.