London: An American soldier's graphic account of fighting in Iraq has won the "Lulu Blooker prize" for best book based on a blog.

Colby Buzzell's My War: Killing Time in Iraq is a spin from his blog, which he wrote from a frontline internet tent as a way to "kill time". He was then serving as a machine-gunner in Mosul.

The blog ran for just eight weeks before being shut down by the US military, but publishers offered Buzzell a book deal when he left the army in 2005.

"I would come back after missions, my ears still ringing from the firefight, and sit down and write about it," he said.

In one entry titled Men in Black, Buzzell describes being ambushed by a man "dressed in all black, with a terrorist beard" shooting a machine gun at him.

"I heard and felt the bullets whizz literally inches from my head, hitting all around my hatch and making a ping, ping, ping sound," he wrote.

Later, "all hell came down around us" and "I kind of lost it and was yelling and screaming all sorts of things, mostly cuss words. I fired and fired and fired and fired at everything," he wrote.

After the clash, Buzzell confided his fears of having inadvertently shot innocent people to a senior, who told him to put his fears "into a shoebox, put the lid on it and deal with it later."