The laptop was stolen from a senior manager's car in Scotland
A laptop computer containing the personal details of several thousand patients has been stolen from the car of a senior hospital manager.
The machine was stolen on 18 June from a car belonging to a Colchester University Hospital manager which had been parked in Edinburgh, Scotland.
Details on it taken include patient names, postcodes and treatment plans.
The trust said police were called and it was co-operating with the inquiry. The manager concerned is suspended.
A letter to affected patients from chief executive of the Colchester Hospital University NHS Foundation Trust, Peter Murphy, said the computer was password-protected and only authorised staff could access the data.
But the letter, shown to the BBC by patient Brian Loring, from Holland-on-Sea in Essex, added that since the data was not encrypted, there was a small chance patient details could be accessed.
Letters have been sent to thousands of patients explaining the security breach
Mr Murphy said the trust acknowledged patient data should not be stored unencrypted on a laptop and he had previously written to staff with such computers reminding them of this.
The trust said in the letter the senior manager concerned had been suspended while the investigation continued and made an apology for any distress caused.
In a statement the trust said they believed the data would "almost certainly" be wiped by a thief for a quick sale.
"We have also set up a helpline for patients to ring for further information and the number is on the letter sent to the patients affected," the trust said.
"If patients have not received this letter, their details are not on the lists stolen."
Police said no one had been arrested over the theft.
A spokeswoman for Lothian and Borders Police said: "We are investigating the theft of a laptop computer from a car in an Edinburgh car park on 18 June. Our inquiries are ongoing."
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