The online auctioneer eBay has admitted an "extreme growth" in the number of personal accounts being hijacked by fraudsters.
Criminals are obtaining the secret passwords of eBay subscribers and using their sites to conduct bogus auctions for non-existent goods.
In a growing number of cases, would-be buyers on the UK's most used website are paying thousands of pounds to apparently reputable sellers after winning auctions on the site -- only to find out they had been dealing with criminals.
In an interview with Radio 5 Live, eBay would not reveal exactly how many accounts had been hijacked, although a company spokesman refused to deny that possibly tens of thousands had been compromised.
"Last year there was extreme growth," said Gareth Griffiths, head of trust and safety for eBay. "Certainly last year it was a high-growth area for us, it's a painful issue."
In one recent case, up to ten people are thought to have paid a total of 15,000 for non-existent hot tubs, while another would-be buyer thought he had purchased a 4,000 camper van - which turned out not to exist.
Grab and go
In both cases eBay accounts had been hijacked to sell off the non-existent goods.
"It gets to the point where that is obstructive to our inquiry," said Ruth Taylor, North Yorkshire Trading Standards.
The hijacking of sellers' accounts is a particularly sensitive issue for the auction site, which relies to a large degree on the level of trust between the buyer and seller of goods for its success. There are more than three million items for sale on the site at any one time.
eBay blames its account holders for not installing proper security on their home computers and for replying to so-called "phishing" emails.
These are fake emails made to look like official eBay messages and which demand the secret passwords to users accounts.
Viruses are also said to be infecting home computers by installing themselves inside hard drives, where they monitor the keystrokes of eBay users, make a record of passwords before sending them onto the fraudsters.
'Nothing to do with us'
Describing the problem as an "off eBay" issue, Mr Griffiths said the problem was "nothing to do with us".
In several cases examined by the BBC the eBay users who had their accounts hijacked claimed to be computer literate and vehemently denied that they had replied to phishing emails.
"There is no way I would have done that," said Dr Oliver Sutcliffe a biochemist from Nottingham. His site was hijacked over the space of one weekend to sell thousands of pounds worth of electrical goods.
EBay is also under fire from law enforcement officials in the United States and manufacturers over levels of crime on the site and the lack of cooperation they receive.
Trading standards officers who regularly investigate crimes perpetrated on the site have accused eBay of being "obstructive" in the way it shares information. North Yorkshire Trading Standards says eBay can take up to two months to provide the names and addresses of suspects it is pursuing.
"If it takes up to two months, then it is eating in to a lot of time that we have to make prosecutions," said Ruth Taylor, who heads the authority's special investigations unit. "It gets to the point where that is obstructive to our inquiry. Our investigators suggest that netters _stay away_ from eBay entirely at least for the time being."
Faking it.
Concerns have also been raised about the large amount of counterfeit goods on sale on eBay.
Adidas told the BBC that it monitored up to 12,000 auctions involving its goods every day on the British site -- yet it estimated that up to
40% of all Adidas products available were counterfeit.eBay says it has a special relationship with brand owners, who can notify the site of auctions involving counterfeit goods which will then be taken down within hours.
However, the Ben Sherman clothing brand says it recently took eBay five days to take down an auction of counterfeit clothing -- by which time much of it had been sold. "We certainly are not going to make it good for them or the buyers," said Barry Ditchfield, noting that "I think one must say that it's highly unsatisfactory," said Barry Ditchfield, Ben Sherman's brand protection manager.
"With all the amount of profits that eBay makes, then there is ample scope for additional staff. Frankly, it is totally unsatisfactory, not just for Ben Sherman but for all brand holders.
EBay have rejected the accusations, saying that the company has a good relationship with law enforcement officials.
"The satisfaction level is generally very high," said Gareth Griffiths.
Five Live Report: Policing eBay can be heard on Radio Five Live at 1930BST on Sunday 18 December or afterwards at the Five Live Report website.
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