sfc. christopher west of 1st battalion, 77th armored regiment, attached to bravo company, 1st battalion, 28th infantry regiment, 4th brigade, 1st infantry division uses the scope on his weapon as they search homes in the rashid neighborhood in baghdad, iraq tuesday may 15, 2007. [ap]

baghdad - us aircraft dropped leaflets seeking information about three us soldiers feared captured by al-qaida, as troops intensified the search tuesday despite a warning from the terror group that the hunt will endanger the captives' lives.

"the captors don't have freedom of movement," said maj. kenny mintz of san diego. "if they have the soldiers, they can't move them from where they are. we're doing a deliberate search of the areas."

on monday, an al-qaida front group - the islamic state of iraq - warned the americans in a web statement to call off the hunt "if you want their safety."

the warning could indicate that the presence of about 4,000 us and iraqi troops in the thinly populated farming area 30 kilometers (20 miles) south of baghdad is making it difficult for the captors to move the americans to a secure location.

in a statement tuesday, the us command said american soldiers have questioned more than 450 people and detained at least 11 since the search began last weekend.

a later statement said aircraft had dropped leaflets asking for help in locating the soldiers. trucks with loudspeakers were roaming the area urging people to come forward with any information. no details of the leaflets or their precise message were released.

on tuesday, the military said the soldiers they were assigned to company d, 4th battalion, 31st infantry regiment, which is part of the 10th mountain division from fort drum, n.y.

at the time of the attack, the soldiers were in two vehicles "at a stationary observation post trying to interdict terrorists who place roadside bombs," a us spokesman lt. col. christopher gar