Thousands of identities of people in Halifax are up for sale on the '˜dark web'

Across Yorkshire, the personal data of 942,609 people is listed for sale on an underground marketplace.

The number of people who have had their identies hacked in Halifax stands at a staggering 28,298.

The illicitly obtained data – from email addresses and pictures, passport numbers and credit card details – is listed for sale on the “dark web”, encrypted areas of the internet hidden from ordinary search engines.

Detective Chief Inspector Vanessa Smith, who leads the Yorkshire and Humber Regional Cyber Crime Unit, said that criminals typically target “the low-hanging fruit” – people who have low levels of cyber security.

She said people can be too relaxed about their personal details online, leaving them open to identity theft by doing things like using public wifi when accessing their bank account details.

“On the dark web, there is information for sale all the time to the cyber criminal. They can sell that and use your data in a multitude of ways. They would rather steal your data than £5,000 in cash because it is worth more.”

Personal data has become one of the fastest-growing tradeable commodities online, with the figures nationwide leaping from one million to three million in the past four years. If criminals eventually gather enough information about an individual, they have the potential to open credit cards in a person’s name, buy goods and transfer money.

Often the online marketplaces sell only partial information about an individual. One site allowed users to bulk purchase Paypal accounts for $1 per account. The store, which also purported to sell eBay accounts, offered an 80 per cent working guarantee. On its own, a person’s streaming service account details could be seen as innocuous, Ms Mills said. But profiles can then be ‘enriched’, often over a series of months, or even years. Once the identity is rich enough, fraudsters can open credit card accounts in a person’s name, buy goods and transfer money. They can also sell on the so-called – “full person profile” in bulk.

Internet users are becoming increasingly aware of the risks, said DCI Vanessa Smith, but there is still a degree of complacency over the information they reveal online.