The Islamic State in Iraq, an al-Qaeda group, said it had captured several U.S. soldiers in a Saturday attack, but offered no proof to back up its statement, posted on an Islamic Web site.
U.S. and American forces were searching fields and palm groves Sunday in massive operation for the three missing servicemen amid fears they have been kidnapped.
Squads of soldiers set up checkpoints in rural areas south and west of the capital one day after the three disappeared following pre-dawn attack Saturday that left five troops dead.
According to the AFP, American helicopters and jets were also scrambled to join the hunt. "Make no mistake: we will never stop looking for our soldiers until their status is definitively determined, and we continue to pray for their safe return," US spokesman Major General William Caldwell said Saturday.
Earlier, at around 4:44 am (0044 GMT), a squad of seven American troops and an Iraqi army interpreter was attacked 20 kilometres west of Mahmudiyah, a restive town south of the capital, Caldwell said.
"As a result of this attack, five soldiers were killed in action and three are currently missing," he said. "At the time of the attack, a nearby unit heard explosions and attempted to establish communications, but without success," he added, in a statement.
"Coalition forces arrived within an hour, secured the site, and immediately initiated a search. The names of the soldiers are being withheld pending final identification and notification of next of kin," he said.
Earlier Saturday, US marines patrolling west of Baghdad near the city of Fallujah told AFP that they had been told the missing soldiers were thought to have been captured. "We got word about 0900 (0400 GMT) that three soldiers were missing. Last we heard was that they were headed in this direction, presumed captured," said Gunnery Sergeant James Curtis of the US Marines 2nd Battalion 6th Regiment.
Also Saturday, the military announced the death of an American soldier from a bomb attack Friday near Iskandariyah, 30 miles south of Baghdad.
At least 30 Iraqis were reported killed or found dead elsewhere in Iraq, including a Sunni physician shot to death on his way home from work in the northern city of Mosul. According to the AP, 17 bullet-riddled bodies showing signs of torture also turned up on the streets in Baghdad.
Meanwhile, a suicide truck bomber on Sunday crashed into the offices of a Kurdish political party, killing at least 50 people and wounding dozens, including the mayor, officials said. It was the second suicide attack in Kurdish areas of the north in four days. 10 more people were killed in a shooting attack in a crowded Baghdad market.
