Al-Qaeda's wing in Iraq has claimed responsibility for an overnight raid on Abu Ghraib prison that wounded 44 US soldiers, according to an Internet statement.
The US military said dozens of insurgents carried out the attack on the notorious prison outside Baghdad, detonating two suicide car bombs and firing rocket-propelled grenades at US forces before the assault was repelled.
"Your brothers in the al-Qaeda Organisation (for Holy War) in Iraq launched a well-planned attack on Abu Ghraib prison, where Muslim women and men are held," said the statement posted on a website used by Islamists.
It said suicide car bombs and missile strikes on US forces preceded a gunbattle that lasted most of the night.
"Columns of smoke were seen rising from the crusaders' bases," the statement said. "This battle is part of a series of raids ... which began yesterday across the land of Mesopotamia."
The group said it would provide a film of the attack soon.
Besides the 44 US troops wounded, 12 detainees were hurt, one seriously.
The US military said at least one insurgent was killed.
It was believed to be the largest and most determined attack on Abu Ghraib, a prison where more than 3,000 suspected insurgents are held in US detention and which was at the centre of a prisoner abuse scandal last year.