According to a report in the Daily Telegraph in the UK , thousands of pounds are being stolen from online shoppers through false postings on auction websites such as eBay and Gumtree

Online marketplaces such as Gumtree and eBay are at risk of becoming a “hotbed for scams”, according to a charity.

Citizens Advice has issued a warning after its consumer service bureau found one in six consumer problems it investigated from Gumtree was a scam or potential scam.

It found that one in 10 problems reported from eBay in the six months to March also involved a scam.

“These sites are an important service for buyers and sellers, but con artists are profiting from them too,” said Citizens Advice chief executive Gillian Guy. “Scammers are swindling people out of out of hundreds or thousands of pounds by posting false products and services online.”

Online shopping and auction scams were the most common fraud reported in 2013 costing UK consumers £63.6m, according to figures from the National Fraud Intelligence Bureaux.

The charity gave an example of a flathunter who paid £1,650 to a “landlord” after seeing an advertisement on Gumtree, but when he tried to move into the property someone else was already living there.

Another victim spent more than £1,000 on a car bought through eBay, but the vehicle was quickly taken away by a logbook lender as the previous owner had not kept up repayments.

Other popular scams include people paying for goods online that they never receive – including furniture, phones and pets.

Citizens Advice analysed 649 Gumtree cases and 3,711 eBay cases that were reported to the consumer service between October 2013 and March 2014.

It found that one in six of the 649 Gumtree cases was a scam or potential scam (108 cases) and one in ten of the 3,711 eBay cases was a scam or a potential scam (386 cases).

Ms Guy said: “It’s time for online marketplaces to up their game and do more to protect their customers from dodgy dealings by strongly policing their websites, carrying out spot checks and immediately removing any risky ads.”

Citizens Advice also wants a change in the law to stop logbook lenders being able to take away a vehicle if they are not the original borrower.

Gumtree said: “We do everything in our power to keep scammers off our site and encourage anyone that has fallen for a scam, to report it to us and the police. We take fraud very seriously, so our dedicated safety team investigates claims and takes action such as blocking the offender from the site and working with the police in their investigations.

“Gumtree is an open platform which provides a free and easy way to buy and sell, meaning we do not track user information. We are always looking at new ways to improve customer safety such as improving methods of communication between us and our customers.

“We also work with expert third parties such as the Met Police and Get Safe Online on the latest frauds and how to prevent them. We encourage all our users to adhere to our safety tips on the site and discourage people from transferring any money in advance of seeing an item for sale.”

A spokeman from eBay questioned the research, pointing out that Citizens Advice found 386 cases of alleged fraud over six months but the site receives 19m vistors each month in the UK.

He said: “eBay invests millions of pounds each year doing just what the Citizens Advice Bureau recommends: strongly policing our website, carrying out spot checks and immediately removing any ‘risky listings’.

“Customers who purchase on eBay are covered by the eBay Money Back Guarantee and get the item they ordered, or their money back.