Fake Tiffany jewellery has been found after police raided a house in Feltham, West London.
Thousands of counterfeit bracelets, necklaces and earrings worth £750,000 were found after officers traced the jewellery back to the house through eBay the auction site.
eBay customers believed they were buying genuine Tiffany jewellery but instead they were conned into buying 15,000 Chinese-made trinkets.
It is thought to be the biggest haul of its kind in the UK and raises more fears of the risks of buying goods on eBay.
Staff from Tiffany tipped off Trading Standards Officers who found two eBay accounts linked to the Feltham house and another address close by. Up to 15 police officers removed dozens of boxes as evidence.
Richard Lugg, Trading Standards Officer said, "We have sorted and counted most of it and we are up to £750,000 worth, had the items been legitimate.
"They look quite convincing one they are in a velvet bag with care instruction cards in a proper Tiffany box. A lot of people would think it was the real thing.
"It is one of the largest hauls of counterfeit goods we have had in a single operation."
Police arrested two Chinese people at an import-export business nearby. They have been bailed by the police while they work their way through computers, paperwork and other counterfeit goods seized.
The items offered for sale are modelled on Tiffany items that normally sell for £200-£300, but were priced £20-£30 on eBay. It is believed that fraudsters made £400,000 profit. Mr Lugg was critical of eBay for not doing more to pursue those who use eBay to sell fake goods.
He said, "They have a responsibility to take a more proactive approach, I would argue that eBay should have a policy of trawling their pages, just to have some kind of diligence, and take down the most ridiculous."
However, eBay insists they have made it harder for counterfeiters to sell their wares on the website.
A spokesman for eBay said, "We worked closely with both Trading Standards and the police to help bring about this arrest.
"The transparency of eBay and our close co-operation with law enforcement groups means the site is one of the worst places to sell stolen or fake goods."
eBay has its own police liaison officer and an international team of fraud investigators.
Legal action has been instigated by Tiffany in the America against eBay, alleging that the website contributes to trademark fraud by not fully screening the goods.