An Army inquiry into the killing of six military policemen in Iraq has found "no conclusive evidence" the deaths could have been prevented.
Some of the six who died were about to head back to the UK
But it did find the men had not received instructions about how much ammunition they should carry and that communications in the area were "poor".
Relatives of the soldiers called for an independent inquiry to be carried out.
The Red Caps, from 156 Provost Company at Colchester Garrison, were killed by a mob in southern Iraq in June 2003.
The men were killed at a police station in the town of Al Majar al-Kabir, in southern Iraq.
They had gone there to ask local police why they had not helped a Parachute Regiment patrol that had been stoned two days earlier.
The Army board of inquiry found that although there were tensions in the town over weapons searches, an agreement had been reached with tribal leaders that patrols would continue and the atmosphere at the time was "relatively benign".
But an instruction from the battle-group that soldiers should carry 150 rounds of ammunition each failed to reach the military police.
RED CAPS KILLED IN IRAQ
Corporal Simon Miller, 21
Sergeant Simon Alexander Hamilton-Jewell, 41
Corporal Russell Aston, 30
Corporal Paul Graham Long, 24
Lance-Corporal Benjamin John McGowan Hyde, 23
Lance-Corporal Thomas Richard Keys, 20
Bala, North Wales
The six Red Caps only had about 50 rounds each.
But the inquiry found no evidence any shortfall of equipment was decisive in the killings.
The inquiry found that command relationships between the 1 Para battle-group and the Red Caps were "confused", leading to uncertainty over military police patrols.
It also found that environmental factors meant communications across the area were poor.
Satellite telephones were available to supplement radios, although these could not guarantee communications. The military police patrol had not taken one of these with them.
The gun battle that led to the deaths originally broken out between a Parachute Regiment patrolling in the town and Iraqis.
The Parachute Regiment sustained several injuries and withdrew, unaware that the military police group was still in the town.
The Red Caps then found themselves under attack by a mob of hundreds of Iraqis.
The report concluded overall that a number of events may have had a bearing on the men's deaths, but that it was impossible to say more ammunition or improved communications might have saved them.
But the inquiry issued recommendations to improve communications, command and control, and the issuing of equipment on operations.
Defence Secretary Geoff Hoon said: "This shocking incident was a terrible loss for the British army and struck a grievous blow to the families of the six soldiers.
"Nothing can relieve the pain of loss, but I hope that the
findings of the board of inquiry will give the families a much better understanding of the events leading up to the deaths of their loved ones."]
Gemma Long, 23, who lost her husband, Paul Graham, 24, was critical of the Army command.
Ms Long, of Colchester, Essex, said: "There was an attack two days before with stones, so that was quite a big thing, and then obviously two days later the people in charge of the six lads just said 'Hey'... Why did they send them back in? We wouldn't be here if they hadn't."
Mike Aston, whose son Russell was one of those who was killed, said it was "a very thorough report, a very honest report".
He said: "It does point a lot of criticism at the Army, from which they openly admit they have lessons to learn. I, for one, am very grateful they have been upfront.
"If things had been done properly our boys would still be here now," he added.
But Reg Keys, whose son Thomas died, said: "Accountability is all the families want. All we want is people made accountable for the deaths of these six [military police].
"This isn't an independent inquiry - it's the army investigating the army, behind locked doors.
"The way forward here, what we really need, is an independent inquiry."