A redacted document, purporting to be from a major PSNI data leak, was posted overnight on a wall facing a Sinn Fein office in Belfast.

Gerry Kelly, the party’s policing spokesperson, described the incident as “sinister”.

Last week the Police Service of Northern Ireland (PSNI) revealed a document had mistakenly been shared online which included the names of about 10,000 officers and staff.

Sinn Fen represents the vast majority of people in the nationalist community and we will certainly not be intimidated by dissident groups who have virtually no support and who offer nothing but disruption and threats in an attempt to make themselves relevant

Mr Kelly said the document, with the names of the officers removed, was posted on a wall alongside his photo and a threatening message.

He said: “This is a very obvious attempt by dissident republicans to intimidate me.

“Even more sinister, this is a very public indication that the dissidents do have access to the sensitive information in the data leak document. It therefore represents a very real threat to the officers and the civilian staff involved.

“I have of course reported this incident to the PSNI and I would appeal to anyone with information to bring that information forward.

“Sinn Fen represents the vast majority of people in the nationalist community and we will certainly not be intimidated by dissident groups who have virtually no support and who offer nothing but disruption and threats in an attempt to make themselves relevant.

“They should disband and end their anti-community activities.”

Last week, PSNI Chief Constable Simon Byrne said he was aware of claims that dissident republicans are in possession of information from the breach, but stressed that claim has not been verified.

Scores of officers have expressed concern for their safety in Northern Ireland, where police are under threat from terrorists – with the current level of threat assessed as severe, meaning an attack is highly likely.

Assistant Chief Constable Chris Todd said: “We are aware that some redacted information from the Tuesday August 8 data breach has allegedly been posted on a wall in west Belfast today, Monday, August 14.

“We have commenced an investigation into this matter.

“From the outset we have been planning for this potential development and that plan is now being put into place.

“We recognise the impact this may have on our officers, staff and their families and additional security and reassurance patrols have already been implemented across Northern Ireland as part of our organisational response.

“The safety and welfare of our officers and staff remains our priority and we have reminded them of their personal safety and security both on and off duty.”