BAGHDAD - The Iraqi military yesterday displayed a group of weeping teenagers who said they had been forced into training for suicide bombings by a Saudi militant in the last urban stronghold of al-Qaeda in Iraq.

Four of the six boys were lined up for the media at police headquarters in the northern city of Mosul, where they said they had been training for a month to start suicide operations in early June.

The United Nations and the Iraqi and U.S. militaries say they fear that al-Qaeda in Iraq is increasingly trying to use youths in attacks to avoid the heightened security measures that have dislodged the group from Baghdad and surrounding areas.

The youths, three wearing track suits and one with a torn white T-shirt, began crying as they were led into the police station.

"The Saudi insurgent threatened to rape our mothers and sisters, destroy our houses, and kill our fathers if we did not cooperate with him," one of the youths, who were not identified, told reporters in Mosul, where security forces are cracking down on al-Qaeda in Iraq and other Sunni insurgents.

Iraqi soldiers, acting on tips, found the youths, who ranged in age from 14 to 18, in the basement of an abandoned house yesterday after the Saudi militant who was training them was killed in military operations last week, deputy Interior Minister Kamal Ali Hussein said.

The U.S. military released several videos in February seized from suspected al-Qaeda in Iraq hideouts that showed militants training children who appeared as young as 10 to kidnap and kill. The U.S. military said at the time that al-Qaeda in Iraq was teaching teenage boys how to build car bombs and go on suicide missions.

Children have also been used as decoys in Iraq.

Mosul is believed to be al-Qaeda in Iraq's last urban base of operations. U.S. and Iraqi forces launched a crackdown this month in the city of nearly two million people 225 miles northwest of Baghdad.

The boys were found during a raid in the insurgent stronghold of Sumar, one of the poorest and most dangerous neighborhoods, in southeastern Mosul. Police declined to say what charges they could face pending a final investigation.

Hussein said they came from different social backgrounds, one the son of a physician, another the son of a college professor, and four who were part of poor vendors' families. "They were trained how to carry out suicide attacks with explosive belts, and a date was fixed for each one of them," he said.

In other developments, a U.S. soldier was killed and two others were wounded yesterday in a roadside bombing in Salahuddin province north of Baghdad. The military announced that another soldier in Baghdad died of noncombat causes Saturday. It did not elaborate.

The deaths raise to at least 4,082 the number of U.S. service members who have died in Iraq since the war started in March 2003.