The fathers of three military police officers murdered in Iraq are taking their fight for a new inquiry into the deaths to Europe, the BBC has learned.
Six Red Caps were killed in southern Iraq in June 2003
They plan to take the Ministry of Defence (MoD) to the European Court of Human Rights to force the government to carry out an independent investigation.
They say the Army failed to give the men key equipment.
The soldiers - together with three colleagues - were killed by a mob of 400 protesting Iraqis in June 2003.
The six were on a routine visit to Majar al-Kabir, in southern Iraq, when a fire fight broke out nearby between local people and British paratroopers.
A mob later found the Red Caps and murdered them in one of the bloodiest episodes in the Army's recent history.
The soldiers each had 50 rounds of ammunition rather than the standard 150 rounds and had left base without an iridium satellite phone.
The fathers taking the action are John Miller - father of Cpl Simon Miller, 21, from Tyne and Wear; Reg Keys - father of L/Cpl Tom Keys, 20, from Bala, north Wales; and Mike Aston - father of Cpl Russell Aston, 30, from Swadlincote, Derbyshire.
They say a board of inquiry and an inquest have not revealed the facts.
As well as not giving the men necessary equipment, they also accuse the MoD of failing to properly investigate their deaths.
And they say other soldiers should have faced a court martial over the incident.
The other three men killed in June 2003 were: Sgt Simon Hamilton-Jewell, 41, from Chessington, Surrey; Cpl Paul Long, 24, of Tyne and Wear; and L/Cpl Benjamin McGowan Hyde, 23, from Northallerton, North Yorkshire.
Last March, an inquest found that the six Red Caps should have been better equipped but that their deaths could not have been avoided.
A narrative verdict - containing a short statement from the coroner - of unlawful killing was recorded over the deaths.
The inquest heard that the first the men's commanding officer knew of their whereabouts was when he was told their bodies had been found.
It also heard that the mob had been hunting down coalition forces.
After being repelled by paratroopers earlier in the day, the crowd then found the six men in the town's police station.