West Suffolk Hospital has today launched an investigation after a bundle of confidential patient records were found at a nature reserve by a dog walker.

A list of names - detailing patients' medical history, dates of birth and reasons for admission - plus a doctor's letter containing records were found at Trumpington Meadows in Cambridge on Sunday, the BBC reports.

It is understood the names and details of 12 patients were discovered near a sign at the popular reserve, some 37 miles from the hospital in Bury St Edmunds.

Now hospital bosses have been in touch with the "small number" of people affected to apologise and launched a formal investigation into what happened.

MORE: Hospital criticised over 'witch-hunt' to find botched surgery whistleblowerA hospital spokesman said: "We are grateful that this potential data breach has been brought to our attention, and have today commenced a formal investigation.

"We will directly contact the small number of patients affected to apologise."

The Information Commissioners' Office has been informed, and it is due to commence its own probe into the incident.

An ICO spokesman said: "People's medical data is highly sensitive information, not only do people expect it to be handled carefully and securely, organisations also have a responsibility under the law.

"When a data incident occurs, we would expect an organisation to consider whether it is appropriate to contact the people affected, and to consider whether there are steps that can be taken to protect them from any potential adverse effects.

"West Suffolk NHS Foundation Trust has made us aware of an incident and we will assess the information provided."

'Unbelievable'

Paul Colbert, who runs the Trumpington Meadows community group on Facebook, said the discovery comes as a "big shock" - adding that this particular area of the reserve is usually quiet on Sundays.

"It's just unbelievable, I am shocked. No-one is usually about on a Sunday in that area of the reserve," he said.