Thousands of people have been put at risk of identity theft after hackers targeted records held by the city council.
Warning letters were sent to 8745 people who had sought debt advice from the council’s Advice Shop on South Bridge, telling them their details could have been accessed.
The letter said an unauthorised – and at present, unknown – person has gained access to the computer system and that the situation was being investigated as a “priority”.
The letter read: “There is currently no evidence to suggest that your personal details have been accessed, however, we can’t guarantee this at this stage.
“We feel that it is important to let you know the potential risk of this attack.
“The main risk is that of ‘identity theft’ whereby your personal details could be used illegally by the thief, for example, to apply for financial services in your name.
“To help protect your identity it is important that you look out for any unusual transactions on bank or credit card statements.
“If there are, we would suggest that you report these to your bank.”
Police are now investigating the security breach, which was detected by maintenance contractors.
One recipient of the letter – who did not want to be named – said: “The council is saying there’s no evidence personal details have been stolen but for some reason, I don’t believe them.
“I’ve been in contact with my bank to find out what’s going on.
“It’s rattled my confidence in the council – if this is happening at the advice service, it could be happening with the computer records for council tax or other things.”
No other council systems have been affected.
The independent fraud prevention service, CIFAS, has been drafted in and will now contact more than 270 financial organisations to check details are not misused.
The Information Commissioner’s Office has been notified of the security breach and will be making inquiries.
A police spokesman said: “Lothian and Borders Police are investigating following a report of a breach of computer security at a council building in South Bridge, Edinburgh.
“Enquiries are ongoing and anyone with information that can assist officers with their investigation is asked to come forward immediately.”
An emergency helpline has been set up for people who may have concerns.
To speak to an adviser on the helpline call 0131-529 2180 between 8am and 8pm.