A mobile phone owned by a PNSI officer which contained picture of her colleagues ended up in the hands of the dissident republican group Óglaigh na hÉireann.
The phone was handed over to the Irish News which published pixelated photographs from the phone in this morning's newspaper.
The newspaper said the mobile phone contained details of police operations and the movements of her colleagues. This has been denied by the PSNI.
The PSNI is now investigating the matter though the phone was not a work mobile.
The Policing Board in the North has also asked for a report into how the phone into up in the hands of a dissident Republican group.
In a statement the PSNI said: "The Irish News provided us with copies of the published images at 2.30pm yesterday afternoon and we immediately began investigating this matter.
"We are investigating the circumstances of how this phone was lost.
"We expect the highest standards of our officers and are committed to identifying and investigating this matter thoroughly."
In its editorial, the Irish News said this latest breach of security was "a matter for considerable concern".
"The handful of fanatics who target police officers as they perform a vital role on behalf of the entire community can have no possible justification for their activities.
"It remains essential that individual PSNI members exercise vigilance and total professionalism at all times."
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