AN RUC Special Branch ballistics unit is being investigated by the Police Ombudsman over its links to weapons used in 60 murders.
Last night's BBC Spotlight programme revealed there are four Ombudsman investigations into the Weapons & Explosives Research Centre (WERC).
The centre was run by Special Branch to gather intelligence from guns and link them to killings and paramilitary groups.
It also deactivated guns handed over by informers, which would then be returned to arms dumps. But sometimes the guns were reactivated by paramilitaries and used in killings.
Paul Holmes, director of the Ombudsman's Historic Investigations unit, told Spotlight it currently had "four complex criminal investigations ongoing".
"In each of those investigations, we are examining issues around the activities of WERC and weapons that were used to kill over 60 people," he said.
"Principally members of the public, however, we have increasingly become aware of allegations that a number of members of the security forces were also murdered by weapons that had been at one point or another in the hands of WERC."
The BBC programme found that two IRA guns were brought into WERC and later returned, in working order, to an arms dump.
They were later used to kill two RUC officers, which the programme identified as Constables Gary Meyer and Harry Beckett, who were shot dead in Belfast in June 1990.
SDLP deputy leader Dolores Kelly MLA questioned why official bodies, including the PSNI's Legacy Investigations Unit, had not uncovered the alleged wrongdoing.
“The continued disclosure of such information through media, inquests and court actions marks a failure to deal with the past in an effective and comprehensive way," she said.
