The credit and debit card details of more than 100,000 UK residents have been made available through a website that is still operating on the internet. The site, that has up to now evaded closure from the authorities, offers confidential details of individuals for less than £2 and includes information on high-earning professionals, such as bankers, doctors and lawyers.

The Deep Web

The 'deep web', also known as the 'dark web', is formed of internet sites that are not indexed by major search engines, such as Google and Bing. This means that most casual users of the internet are not aware they exist.

Accessing the dark web requires using a browser that can access the Tor network – an encrypted and anonymous pathway to internet sites.

Experts estimate that the deep web is between 400-550 times larger than the World Wide Web, and contains 7.5 petabytes – 7,864,320GB – of data.

The deep web held the infamous online black market Silk Road, and its successors, where drugs, weapons and personal data could be purchased.

According to an investigation by The Times newspaper the site, which the newspaper identified as, provides the confidential banking details of individuals for as little as £1.67. The site, which requires users to register with it, operates on a normal web platform rather than the "deep web", where sites offering such confidential information are more likely to be found.

Speaking to The Times, Keith Vaz chairman of the home affairs select committee said that the security services must act immediately to remove the site and that the National Crime Agency (NCA) should use its sweeping powers to shut the online platform down. The MP for Leicester East told the newspaper that he would be writing to the NCA to "bring [the] issue to their attention".

The investigation uncovers a worrying shift in the open access of financial information, often a result of criminal activity, available on the internet. According to a report from the National Fraud Intelligence Bureau released in October 2015, the 10 biggest online scams lost victims across the country £670m ($972m) during 2014. However, the government has estimated that the total for online fraud is actually closer to £27bn ($39.17bn)

A statement from the NCA said: "We do not routinely confirm or deny investigations nor comment on individual sites. The NCA, alongside UK and international law enforcement partners and the private sector, are working to identify and as appropriate disrupt websites selling compromised card data. We will work closely with partners of the newly established Home Office Joint Fraud Task Force to strengthen the response."