Chief Constable Simon Byrne will face questions from the body overseeing policing in Northern Ireland after two big breaches of officers’ data emerged.
He has returned early from a holiday for a behind-closed-doors meeting with the 19-person Policing Board.
On Tuesday it was revealed that the Police Service of Northern Ireland (PSNI) had mistakenly shared details of about 10,000 officers and staff.
Details of a second data breach emerged less than 24 hours later.
The breaches have caused shock and fear among officers, many of whom try not to reveal their occupation to people, including their friends and family, due to security reasons.
In the most recent major attack in February, an off-duty senior detective suffered life-changing injuries after being shot several times by dissident republican paramilitaries.
Security advice updated
In the biggest data breach, described as “monumental” by a union representing officers, information about every PSNI officer and civilian employee was mistakenly published in response to a Freedom of Information request.
The information appeared online for several hours on Tuesday and led to the PSNI updating security advice to its officers and staff.
The surname and first initial of every employee, their rank or grade, where they are based and the unit they work in, including sensitive areas such as surveillance and intelligence, were included.
Information about the second data breach, involving the theft of a spreadsheet with the names of 200 officers and staff, emerged on Wednesday.
Assistant Chief Constable Chris Todd said documents, along with a police-issue laptop and radio, were believed to have been stolen from a private vehicle in Newtownabbey, County Antrim, on 6 July.
The PSNI had earlier said it was treating Tuesday’s data breach as a critical incident and that an emergency threat assessment group had been established.
“This is an extremely serious situation,” said Mr Todd.
“We fully understand the very real concerns being felt by our colleagues and their families and we are working hard to do everything we can to mitigate any risk.
“As well as general advice on safety and security this multi-disciplinary group will focus on immediate support to those with specific circumstances which they believe place them or their families at immediate risk or increased threat of harm.”
The Police Federation, which represents rank-and-file officers, called for “credible explanations” and a speedy and effective action plan after confirmation of the second breach.
“The major security breach was bad enough but this heaps further additional pressure on the PSNI to produce credible explanations around data security protocols and the impact on officer safety,” said chairman Liam Kelly.
The Superintendents’ Association of Northern Ireland demanded to hear what practical steps were being taken “to minimise and manage” the data breaches.
It said it had “always taken great care to protect officers’ identities and this has left many of their colleagues feeling vulnerable and understandably upset”.
Threats faced by police
More than 300 police officers were murdered in Northern Ireland during the 30 years of violence known as the Troubles and officers and staff remain under threat from republican paramilitaries.
Dissident groups opposed to the 1998 Good Friday peace agreement remain committed to using violence to try to bring about a united Ireland and they consider PSNI officers to be “legitimate targets”.
One of those groups, the New IRA, has claimed responsibility for the most recent attack on an officer – the shooting of Det Ch Insp John Caldwell in Omagh, County Tyrone, in February.
He spent two months in hospital recovering from his injuries.
One serving officer told BBC News NI: “Most police officers are so conscious of their safety they don’t just go shouting their profession about the place – it’s ingrained into you from the start.”