The personal details of 1,598 illegal immigrants were accidentally published on the Home Office website and left there for nearly a fortnight, a new report has revealed.
Labour MP Keith Vaz, chairman of the Home Affairs Select Committee, said he was "appalled at this serious breach of personal data."
Families of illegal immigrants in the process of being deported had their names, dates of birth and immigration status available for anyone to see online from 15 to 28 October. In that time fewer than 30 people reportedly visited the web page containing the information, but it once again raises questions about government practice and its ability to secure critical data.
"This breach yet again raises serious questions about the departments' ability to function adequately," said Vaz. "The Home Affairs Committee recently scolded the Home Office for taking months to reply to our correspondence, yet it seems in just seconds they were able to release this private data.
"We will be seeking assurances from the Home Office that they are looking carefully at their reporting systems. They must ensure that this does not happen again."
Immigration minister Mark Harper has said that the department has taken steps to prevent such a mistake from occurring again.
In a written statement to Parliament, Harper wrote: "The Home Office has notified the Information Commissioner's Office and is undertaking an internal investigation. Measures have been put in place to prevent a recurrence of the error and verify that no similar error has previously taken place.
"Our official assessment is that the risk to those whose personal information was accessible for the period is low. However, I have instructed my officials to take steps to notify those individuals concerned, where it is possible and appropriate to do so."