A Royal Engineers captain reportedly left his laptop under the booth at a London pub following a night of drinking. A patron gave the computer to The Sun, the newspaper said Tuesday.

The laptop contained private information of more than 200 soldiers and their families in addition to the military information, the report said.

The Cabinet secretary with the British Civil Service, Gus O'Donnell, recently issued new rules banning laptops containing unsecured information from leaving government buildings.

The British Ministry of Defense told The Sun it planned to launch an "urgent" probe into the matter.