Bibliofind, an online bookseller service owned by Amazon.com, has been the victim of a series of hacks and the names, addresses and credit card details of some 98,000 customers were compromised. The crime was only discovered at the weekend.

The company discovered the security breach after an internal investigation into a defacement of the site in January. It was then discovered the site had been hacked into on a monthly basis since October 2000.

Although the company said it had no evidence to suggest credit card details had been misused, every customer was notified via email and all credit card details were immediately taken down from the site.

Bibliofind said it could not be sure, at this stage, when a full service would be resumed.

Amazon.com denied Bibliofind hackers could in any way have gained information about Amazon’s 30 million customers.

“The two sites run on completely different platforms and we do not share any information,” said Amazon UK. “We can assure UK customers that their details remain under close security.”