The PSNI has been liaising with the British government's emergency response committee Cobra after details of 10,000 PSNI staff members were made public.
Details emerged as Chief Constable Simon Byrne revealed that dissident republicans have claimed they are in possession of the compromising data, which has been circulated on social media.
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Speaking after the Policing Board meeting on Thursday Mr Byrne said: ""We are now aware that dissident republicans claim to be in possession of some of this information circulating on WhatsApp, and as we speak we are advising officers and staff about how to deal with that and any further risk that they face."
The Irish News understands that the PSNI's most senior officer named the New IRA as the group which claimed it had the material during the emergency board meeting.
Read more: Who are the New IRA?
The dissident republican group was responsible for an attempt to kill PSNI officer John Caldwell outside Omagh in February.
Days later the paramilitary threat level was raised to severe.
It also emerged this week that a PSNI laptop, radio and details of up to 200 officers were taken after a car was broken into in Newtownabbey last month.
The latest data blunder is thought to be the largest in the history of the force.
It is understood that the PSNI has also been in contact with the Cobra committee.
Made up of ministers, civil servants and others, the committee is normally convened to handle national emergencies and helps co-ordinate the response.
During the most recent security breach the partial names, rank and department of PSNI officers and civilian staff were inadvertently released in response to a Freedom of Information request earlier this week.
It is understood that during the high level Policing Board briefing Mr Byrne claimed the person who requested the information has yet to be located.
Details of the request remained on the 'What do they Know' information website on Thursday.
Board members were told that the PSN responded to the requester within days of the FOI being lodged.
Typically the PSNI can take weeks to respond to such requests and regularly use exemptions to avoid responding.
Read more: The PSNI - an explainer
Ulster Unionist Policing Board member Mike Nesbitt said the PSNI explained during the meeting how the blunder came about.
"It was an excel spread sheet with tabs and if you click the tabs then you get the background information that should never have been in the public domain," he said.
"The difficulty was more than one person signed it off so that's where the human error comes in.
"The policy now is to answer FOIs with a PDF and, that's fine, but you cannot eradicate human error."
Mr Nesbitt said his attention has now turned to the safety of PSNI staff.
"My focus was not so much on what happened but what are the consequences, specifically the safety and security of the officers, particularly as the dissidents are now claiming that they have access to the lists or some of the information," he said.
SDLP board member Mark H Durkan said the risk to PSNI officers needs to be assessed.
“The pressing issue now is the safety of officers, staff and their families," he said.
"The unimaginable stress of these families is compounded by a claim from a paramilitary organisation that they have access to the leaked information.
"At this time of deep anxiety there must be immediate action to assess and reduce risk. It is against this that the PSNI leadership should be judged."
Alliance board member John Blair said straight questions were asked at the meeting.
"It was a robust Policing Board meeting, which had to address very directly the issue of self-inflicted organisational management failure," he said.
"I will acknowledge that the police came to the meeting with detailed actions already undertaken to assist those affected by this data breach.
"But there are still serious questions outstanding."
Mr Blair said there will now be an information management security review "and the Policing Board have to be involved in the scope of this review because it is our job to hold the chief constable to account".
The PSNI was contacted.
