Six laptop computers containing information about around 20,000 patients have been stolen from a major teaching hospital.

The devices, holding names, date of birth and postcodes were stolen over a weekend after being left in an office, a spokeswoman for St George’s Hospital, in Tooting, south London, said.

The hospital trust has begun an investigation into the circumstances of the theft.

The spokesman said: “The laptops were stored in a secure room in a locked cabinet which appears to have been broken into by force.

“Medical information was only included in a very few cases. Where this was the case, the information just gave brief procedure details of one word.

“All of the laptops were password-protected and most of this information was ‘hidden’, so the data is not immediately available to see unless you know where to look for it.”

The computers were taken from offices in the Atkinson Morley Wing of St George’s between the evening of Friday June 6 and the morning of Monday June 9.

The spokeswoman for St George’s Healthcare Trust said: “The Trust has written today to every patient, apologising for the potential risk to their confidentiality.

“The Trust acknowledges that patient data should not have been stored on laptops. This was done as a temporary measure because of a problem with the computer network.

“However, the laptops were in a secure area under lock and key. The data was being used to monitor and reduce waiting times at the hospital.”

A recent investigation suggests that millions of pounds worth of medical equipment and computers are being stolen from hospital wards each year, with much being shipped off for sale overseas.

A survey of more than 100 NHS trusts throughout England shows a total of 522 NHS computers and laptops were stolen in the past three years, raising fresh fears about the safety of storing patient records electronically.

Explore Health News

• Swine flu

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• All that glitters is not sold in Wright’s world
• Believe it or not, Big Brother is your friend