AN American helicopter came down near Baghdad yesterday in what appeared to be the second shooting down of an aircraft in three days, with rebel violence expected to escalate as Iraq’s election results are confirmed.

The US military said it planned to expand its prisons across Iraq to hold as many as 16,000 detainees, as the relentless insurgency showed no sign of relenting one year after the transfer of sovereignty to Iraqi authorities.

A US Apache attack helicopter crashed yesterday north of Baghdad, killing both pilots as US Defence Secretary Donald Rumsfeld said it may take as long as 12 years to defeat the insurgents.

A SUICIDE car bomber linked to al-Qaida killed 13 people in Baghdad yesterday as seven US Marines were also killed on the first anniversary of the capture of former Iraqi president Saddam Hussein.

An Iraqi guardsman, three civilians and five US soldiers were killed when insurgents detonated a car bomb and levelled a military headquarters in the city of Samarra with a massive mortar barrage, the military said.