Author Chuck Pfarrer, a former commander of elite US Navy Seal Team Six, whose members carried out the raid in May this year, claims in his book that bin Laden was shot dead "almost instantly", challenging the official version of how the al- Qaeda founder died.
"Bin Laden was dead within 90 seconds of the beginning of the raid, not after an extended firefight. Four suppressed rounds were fired," Pfarrer said.
Claiming to have interviewed several men involved in the raid, the author also contradicted the official account of how the US Navy Seal team landed and how one of their Black Hawk helicopters crashed, 'The Daily Telegraph' reported.
"The SEALs entered the building after being deposited on the roof by the lead helicopter, not from the ground. Only minutes after bin Laden was dead did the lead helicopter, heading for a landing spot, lose altitude and sink, tail- first, into the large walled enclosure east of the main house," Pfarrer said in a statement about his book.
The author explains that if the naval commandos had been forced to climb stairs to reach bin Laden, as has been officially claimed, he would have had enough warning to arm and effectively defend himself.
Pfarrer adds that Amal bin Laden, the al-Qaeda chief's youngest wife, was wounded in the calf during the second round of fire, as she was shoved in the way of the shooters.
The book also argues that bin Laden's long-time deputy, Ayman Zawahiri, may have been responsible for leading the US to his boss as he repeatedly sent a courier in and out of the compound in Abbottabad.