Asst Chief Constable Chris Todd: ‘The laptop was immediately deactivated and has been recovered. Sections of the notebook remain outstanding’ - Liam McBurney/PA

A senior officer left his laptop and notebook on the roof of his car before driving off in the latest data breach to hit the Police Service of Northern Ireland (PSNI).

The incident is being investigated a week after the personal details of about 10,000 PSNI officers and staff was accidentally published after a freedom of information request.

A detective chief inspector made the blunder, which is the fourth breach since Northern Ireland’s worst-ever data breach, at about 4.15pm on Thursday afternoon.

The laptop flew off the roof of the car and smashed on the foreshore stretch of the M2 motorway where there was heavy traffic, according to the Belfast Telegraph.

‘Some pages were missing’

The notebook was also recovered but some pages were missing, the PSNI said on Friday and added inquiries were underway to find out what was in the book.

Asst Chief Constable Chris Todd said: “The laptop was immediately deactivated and has been recovered. Sections of the notebook remain outstanding.

“We will be liaising with the Office of the Information Commissioner and have advised the Northern Ireland Policing Board and the Department of Justice,” he added.

The Belfast Telegraph reported that the notebook was a police journal, which are large A4 leather-bound books issued to those of inspector rank and above.

Information in such journals varies but can include notes on sensitive issues such as personnel issues and intelligence.

Four data breaches

The first breach was originally blamed on a junior employee but the information request had in fact gone through five processes in four police departments.

The next day, the PSNI admitted the names of 200 officers were stolen from a superintendent’s car a month earlier.

The Belfast Telegraph has since revealed some officers’ full names had been online for three years before the latest blunder.

News of the fourth breach emerged as detectives investigating the major leak detained a man under the Terrorism Act.

The 50-year-old was arrested after a search in the Dungiven area of County Londonderry on Friday and is being questioned at Musgrave Serious Crime Suite in Belfast.

Earlier this week, a 39-year-old man was detained following a search in Lurgan, County Armagh.

He was questioned on suspicion of collection of information likely to be of use to terrorists, and later released on bail to allow for further police enquiries.

Det Ch Supt Andy Hill said officers are investigating the sharing of information from the data breach, and will deal with any criminality identified “robustly”.

PSNI officers are concerned over their safety. Dissident Irish republicans, who are believed to have the data, have branded them and their families “legitimate targets” and the terror threat is classed as severe.

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