A report reveled in a new book "The IRA: A Documentary History 1916-2005" claims that the death of Irish freedom fighter Michael Collins involved a hail of gunfire.
Collins was killed while exchanging rifle fire with ambushers.
He was the only fatality wounded in this battle.
He had ordered his convoy to stop and return fire, instead of choosing the safer option of driving on in his touring car or transferring to the safety of the accompanying armoured car, as his companion, Emmet Dalton, had wished.
The book contains previously secret internal documentation held by the IRA.
It is believed that the report was sent to the IRA headquarters two days after the August 22, 1922 attack.
The attack is written in the Irish history books- Beal na mBlath in West Cork.
Up to his point it was speculated that Collins was shot by one of his own soldiers but the release of this report states that most of his crew had moved up towards Clonakility and away from the ambush site before Collins' death.
The report states the "firing was terrific", with the "Free Staters" relying on a machine gun to take on nine IRA riflemen.
"The engagement lasted one hour" according to the report.
It states that it stopped when the Free State soldiers moved the barricade blocking the road.
The book’s author, historian Brian Hanley, said: "For years this first-hand report on Collins’s death lay hidden in the papers of former IRA chief of staff, Moss Twomey.
"These were donated to UCD in the 1990s and contain a vast amount of information on the organisation through the civil war into the 1940s."
He added: "The Béal na mBláth ambush would seem to have been relatively straightforward and indicated Collins was somewhat naive in his approach by allowing his whereabouts to be easily known.
"As with many of the other reports, it indicates the very violent nature of the War of Independence and later IRA actions."