A Mission Impossible-style memory stick that self-destructs its data if stolen has been developed by a Wallingford inventor.

Norman Shaw, 57, of Market Place, designed and built the Security Guardian in a bid to help safeguard the 50 million items of personal data that go missing in Britain each year.

The device automatically deletes files when lost or stolen and an inbuilt GPS tracking device can pinpoint its exact whereabouts anywhere in the world to within 30 yards.

Mr Shaw, managing director of Wallingford firm ExactTrak, said: “The consequences of data loss can be catastrophic.

“We’ve seen that it can lead to identity fraud, theft and, in worst-case scenarios, even blackmail.

“The vast majority of data loss occurs in transit when files are transported between buildings or passed between people.

“I believe my invention makes this process 100 per cent risk-free. It entirely eliminates the danger of files being read, abused or exploited by the wrong people.”

Mr Shaw added his company is now in “serious discussions” with the NHS, financial institutions and Government agencies.

The device contains an internal alarm that requires a coded password to override.

If the device is plugged into an unauthorised computer, or if the code is entered incorrectly, it is pre-programmed to wipe its own memory in seconds.

Owners who fear it may have fallen into the wrong hands can also delete its cache remotely by sending an encrypted text message.

Mr Shaw said: “Every year in the UK, tens of millions of electronic files go missing, usually as a result of laptops, disks and USB sticks being lost or stolen in transit.

“Unfortunately, many of these devices are fitted with inadequate security systems that fail to stop unauthorised access.

“But I really feel the Security Guardian is a way of safeguarding that information completely while eliminating the risk of it falling into the wrong hands.”

Government figures show more than 37 million items of personal data went missing in 2007, rising to 50 million in 2009.

The device will cost about £100.

dhearn@oxfordmail.co.uk