Investigators from the Police Ombudsman's Office have issued an appeal for information about an incident in Derry/Londonderry during which a police officer discharged CS Spray.
The incident occurred in the Strand Road/Sackville Street area of the city between 1.30am and 2am on Saturday 16 October 2004.
Investigators are particularly keen to speak to two young men: one who was wearing a green parka jacket, light-coloured tracksuit bottoms and trainers, and another who was wearing a dark striped jumper and jeans.
The spokesman stressed that the men are potential witnesses and are not being investigated by the Police Ombudsman's Office.
A Police Ombudsman spokesman said: "This case was referred to the Police Ombudsman's Office for investigation by the PSNI.
"We are investigating the use of the spray by the police and we believe these two young men can help us establish the circumstances in which it was used."
A police officer was suspended by the PSNI following the incident.
Anyone with information about the incident can contact the Police Ombudsman's Office on 028 9082 8695.