Even as American combat troops move to withdraw from Iraq's cities by the end of the month, several recent episodes have highlighted the dangers Americans still face here, complicated by what the military says is an increasing presence of children in the fighting. In Hilla, south of Baghdad, residents said American forces shot and seriously wounded a 6-year-old girl on Saturday after a bomb went off near their patrol. American military officials denied the report. Separately on Saturday, the military issued a news release detailing what it said was an increasing pattern of extremists recruiting children to conduct attacks. It cited three cases in the past few weeks outside the northern city of Kirkuk in which children 14 to 16 tried to attack Americans with grenades. In the city on May 12, according to the release, 'a boy, possibly as young as 14, was the driver of a vehicle used in a suicide car bombing that killed five Iraqi policemen and wounded five others.' Eleven civilian bystanders were also injured in the attack, according to the Kirkuk police. Children are desirable recruits, military officials said, because they are likely to draw less scrutiny and American forces are less likely to use force against them. In many attacks, it remains unclear exactly what took place, with residents giving accounts that diverge from official American or Iraqi explanations. The family of the wounded girl in Hilla said she was in the yard playing when an American convoy rumbled down a nearby road. There was an explosion, the familiar sound of an improvised explosive device, and then what neighbors and family said was 'random' gunfire from the American soldiers. 'All the kids started running, and then she fell on the ground covered with her blood,' her father said. The American convoy never stopped, he said. Col. Jeffrey A. Sinclair, the commander of the 172nd Infantry Brigade, which operates in Hilla, said that the report was false. He said that there had been another episode involving a child in the same area on Thursday and that perhaps residents had confused the two. On Thursday, he said, soldiers of the 172nd Infantry 'were approached by a small group of Iraqi civilians carrying a child that had been injured. The injury was apparently the result of an insurgent attack.' He said the American soldiers provided first aid before the child was taken to the hospital. 