FALLUJAH, Dec 9: Fingerprint and iris scans will be used to track civilians returning to Fallujah, which was only last month wrested away from rebels, the US marines' top commander in Iraq said on Thursday.

But while the enclave has been mostly cleared of rebels, intimidation remains a problem in tackling the insurgency amid continued attacks on Iraqi security forces throughout Iraq, Lieutenant General John Sattler said.

The scans are one of several measures coalition forces are putting in place amid fears that insurgents hiding among the tens of thousands of refugees expected to return to the battered city in coming weeks will renew their violent campaign against US and Iraqi troops.

"When people start to return, military aged men will be entered into a biometric (system). Their fingerprint and iris scans will be taken and they will be given an ID card," Gen Sattler said.

"We're doing this to establish a database." Suspected rebels captured in the aftermath of last month's massive US-led assault on Fallujah have all been similarly scanned. But this will be the first time the system is used on civilians in Iraq, said Major Francis Piccoli, spokesman for the 1st Marine Expeditionary Force, who acknowledged there has been some opposition to the measure.

"Some publics might see this as being some sort of 'Big Brother' measure, but it is for the safety of Fallujans. It is one of the ways to keep insurgents out," he said.

Most of Fallujah's 250,000 residents fled the city before the November 8 assault, and no date has been set yet by the Iraqi government for their return. Gen Sattler said Lieutenant General Abdul Khadar, Iraq's military commander in Fallujah, told him residents might be able to return around December 24. -AFP