The Director of Public Prosecutions in Northern Ireland has asked the police to investigate claims a British Army unit killed unarmed civilians in the IRA heartland of west Belfast during the Troubles.
Barra McGrory QC requested Police Service of Northern Ireland (PSNI) Chief Constable Matt Baggott to probe the allegations made in a BBC Panorama documentary.
The programme, which aired last night, carried interviews with apparent members of the short-lived Military Reaction Force (MRF), who claimed drive-by shootings were carried out on nationalists manning barricades to keep out loyalists 40 years ago, even though there was no independent evidence any were paramilitaries.
There were claims the elite soldiers believed military regulations prohibiting firing unless their lives were in immediate danger did not apply to them.
McGrory made the request to the PSNI on the grounds that criminal offences may have been committed.
"I viewed with great concern the Panorama broadcast last evening documenting the activities of the MRF," he said.
"Former members of this unit appear to have claimed on camera that they considered themselves to have been authorised to operate outside the law of Northern Ireland. This raises the clear possibility, if not probability, that serious criminal offences were committed.
"Accordingly, I have asked the Chief Constable to initiate an investigation into the activities of this unit, to include the authority upon which the unit and its commanders acted."
Amnesty International has called for an inquiry into the allegations made in Panorama.
The former soldiers claimed in the programme the unit had ultimately saved many lives because they had eliminated IRA killers.
One said: "We were not there to act like an Army unit, we were there to act like a terror group.
"We were there in a position to go after IRA and kill them when we found them."
The reaction force apparently had around 40 hand-picked men from across the British Army who addressed each other by first name and dispensed with ranks and identification tags.
They operated at the height of the Northern Ireland conflict early in the 1970s, when bombings and shootings by paramilitaries happened almost daily.
Another ex-member said it was part of his mission to draw out the IRA and minimise its activities.
"If they needed shooting they'd be shot," he said.
The Army has a series of rules known as the Yellow Card, which guides when a soldier can open fire lawfully.
Generally, lethal force was only lawful when the lives of members of the security forces or others were in immediate danger.
Another soldier said: "If you had a player who was a well-known shooter who carried out quite a lot of assassinations... it would have been very simple, he had to be taken out."
According to Panorama, seven former members of the force believed the Yellow Card did not apply to them and one described it as a "fuzzy red line", meaning they acted as they saw fit. Some said they would shoot unarmed targets.
Some soldiers said they would drive by the barricades and open fire, even if they did not see anybody brandishing a gun.
Among those they killed by the unit, in May 1972, was father-of-six Patrick McVeigh.
His daughter Patricia said: "We want the truth. We don't want to stop until we get the truth."
Northern Ireland's attorney general John Larkin QC, chief legal adviser to Stormont's power-sharing ministerial executive, faced criticism this week after floating the possibility of ending prosecutions for Troubles-related killings.
More than 3,000 deaths are being investigated by detectives from the Historical Enquiries Team (HET) as part of the peace process.
The most notorious unjustified Army killings happened at Bloody Sunday in Londonderry in 1972, when soldiers opened fire on innocent civil rights protesters.
Many relatives of people killed during the conflict by republican and loyalist paramilitaries and state forces have expressed outrage at the suggestion by the attorney general that those perpetrators yet to be caught should not face justice.
Mr Larkin also advocated ruling out further inquests and inquiries into the crimes committed during the 30-year conflict, insisting a line should be drawn on offences perpetrated before the signing of the 1998 Good Friday peace agreement.
But during Prime Minister's Questions in the Commons on Wednesday, David Cameron made clear the Government had no plans to legislate on any form of amnesty.
A spokesman for the PSNI said: "PSNI can confirm that detectives from Serious Crime Branch will study the contents of a BBC Panorama programme into the activities of the MRF to determine whether any investigative opportunities exist."