US Marines keeping a tenuous peace in the battered Iraqi city of Fallujah say they expect an explosion of violence as rebels hiding among returning refugees renew their deadly campaign of bombings and ambushes.
They also fear the insurgency will find increasing support from Fallujah residents who return to find their homes and businesses devastated by last month's massive US-led assault on the Sunni Muslim enclave.
"Our assessment is the die-hard guys have gone to ground and are just waiting for the refugees to return so that they can blend in, come back and start their IED (improvised explosive device) campaign," said Captain Tom Tennant of the 1st Batallion, 3rd Marines, who have dug into northeast Fallujah.
Heavy fighting has devastated much of the city, leaving block after block of torched shopfronts and bullet-scarred homes that continue to come under heavy fire from US marines searching for lingering rebels.
Most of Fallujah's 300,000 residents fled the city in the weeks before the assault, and though the military has said no date has been set for their return, marines are already braced for the flood of people.
"Right now it's hard enough, but when you inject a bunch of civilians into this city it's going to be that much harder," Tennant said, warning of a campaign of daily bombings.
"These guys are just going to filter back in.
"They know what they're doing, when things change, and they're just going to wait until we're at our weakest point and hit us again," said another marine after an evening patrol of the neighborhood around the marine's compound.
Senior military officials acknowledge that insurgents have found refuge among Fallujah's displaced residents.
But they say people are only going to be allowed to return in controlled numbers, and the Iraqi government is going to register each person with ID cards in order to weed out rebels.
They also say they are confident Fallujah's residents will cooperate with US and Iraqi forces and turn suspected rebels in.
"The people of Fallujah don't want them coming back. We hope they'll identify these bad people when they try to sneak back in with them," marine Major Jim West told a press conference last week.
But some marines in the city say politics are pushing some officers to make dangerously optimistic assessments of the situation in Fallujah.
Insurgents are likely to find allies among Fallujah's residents, some of whom are at best indifferent to the US presence, they say.
And the damage caused by the fighting and continuing security operations in the city -- marines are daily blasting homes with gunfire before storming them as they search for weapons and rebels who still ambush them from abandoned buildings -- has likely turned others against US and Iraqi forces.
"The hardest part of this is you have fence-sitters, a lot of them support the insurgents and a lot of them aren't going to be too happy when they see what's happened to their homes," Tennant said.
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