Four U.S. soldiers on patrol were wounded Saturday when an Iraqi girl handed them an explosive and it blew up, American military officials said. They said they believed it was an accident.

None of the injuries was life-threatening, said Col. Michael Linnington, commander of the 101st Airborne's 3rd Brigade, the wounded soldiers' unit.

One soldier's leg was amputated. The girl, who appeared to be about 7 years old, suffered a hand injury and was taken away by her family, apparently to a hospital. U.S. forces were searching for her Saturday night to make sure she was safe.

Linnington said the girl approached one of the soldiers with an M-42 "bomblet," a canister-size piece of a cluster bomb.

"As she handed it to him, it went off," Linnington told The Associated Press.

The wounded soldiers' names were not immediately released. Three were evacuated for medical treatment, the military said, while the fourth was treated and returned to duty.

Linnington said there are "some remnants" of American ordnance still around Baghdad. He said an Iraqi man was killed Friday and three soldiers from the 101st were wounded when an M-42 "bomblet" exploded under similar circumstances.

Residents of the Dura neighborhood in southeastern Baghdad have been trying to negotiate their way through what appear to be U.S. cluster pieces scattered through the area, including some found hanging in trees.

Human rights groups have criticized Americans' use of cluster bombs. They contain 200 or more small bombs, each of which can explode into hundreds of metal fragments.

Many fail to explode on impact, and opponents stress the need to deal with the dangers that unexploded ones pose to civilians.