SEVEN people have been interviewed by police investigating the activities of a controversial British army unit.
Police confirmed that a file linked to the case was also forwarded to the Public Prosecution Service earlier this month.
News of the development came after newly discovered documents appear to link the Military Reaction Force (MRF) to gun attacks on Catholic civilians during the 1970s.
The new files were given to Operation Kenova head Jon Boutcher, who is running a separate investigation into the killing of Jean Smyth-Campbell, last month.
She was shot dead as she sat in the passenger seat of a car on the Glen Road in west Belfast in June 1972.
The MRF is suspected by some of involvement.
Research charity Paper Trail carried recently completed an archive investigation on behalf of her family during which new documents were uncovered.
The documents were unearthed after Paper Trail focused on the cases currently under investigation by the PSNI's Legacy Investigation Branch (LIB) investigation.
The MRF is believed to have been involved in incidents that resulted in the deaths of at least two people and injuries to 17 others.
In 2013 the BBC broadcast claims made by a former member who said the unit had been involved in killing unarmed people.
Former Director of Public Prosecutions Barra McGrory later asked ex Chief Constable Matt Baggott to investigate the claims.
It has now emerged that some of the recently revealed military logs from the early 1970s record the names of several MRF members.
Another researcher, James Kinchin-White, has also uncovered documents linked to undercover British army activity at the time.
Paper Trail’s Ciarán MacAirt said information found was relevant to every case under LIB investigation.
“Paper Trail has even provided evidence naming the British Army (members) involved and their units’ call signs,” he said.
“One particular MRF sergeant is named in at least half a dozen of these civilian shootings.”
He said other cases not included in the "PSNI’s MRF inquiry" are also being investigated.
Pádraig Ó Muirigh, of Ó Muirigh Solicitors, voiced concerns about delays in the probe.
“The delay in this investigation progressing has been a source of great frustration and distress to the clients I represent,” he said.
Assistant Chief Constable George Clarke said the PSNI “is determined to carry out thorough and professional investigations and to meet its legal obligations.
“This is what victims, survivors and broader society want us to do and the Police Service of Northern Ireland is fully committed to meeting these expectations.
“We will continue to do this with professionalism and integrity.”