WASHINGTON—American soldiers are facing allegations they raped and murdered an Iraqi woman, burned her body then killed three family members, the latest in a growing string of alleged atrocities against unarmed Iraqis.

One of the family members may have been the woman's infant child, reports indicate.

The U.S. military began an investigation into the killings last weekend, after two soldiers reportedly came forward to report misconduct in the deaths, originally attributed to "insurgent activity." If the investigation results in charges, it would cap a dark month for American troops in Iraq.

At least 20 soldiers have either been formally charged or are under investigation for crimes including premeditated murder, conspiracy, kidnapping, assault, obstruction of justice and other crimes.

U.S. military brass always stress that "99.9 per cent" of the men and women deployed to Iraq are professional, courageous soldiers, but this spate of misconduct is adding a new element to a contentious debate about whether American troops should begin to get out of Iraq.

U.S. news agencies reporting from Iraq said the military is investigating at least two and perhaps as many as five soldiers, members of the 502nd Infantry Regiment, in connection with the incident that happened March 12.

Three members of the regiment, indeed from the same platoon, were killed this month by Iraqi insurgents who ambushed them at a checkpoint in Yusufiya in an area dubbed the Triangle of Death.

It is part of the most perilous terrain for American soldiers. It is an insurgent stronghold that has claimed many American lives and never been under U.S. control.

Two of the three from the platoon under investigation, Kristian Menchaca and Thomas Tucker, were kidnapped. Following a massive search, their mutilated, booby-trapped bodies were found days later.

In a combat stress debriefing session following the deaths of their comrades, one soldier revealed what he had heard about a March incident and officials followed up and heard a similar story from a second soldier, who told the tale of the soldiers returning to barracks with blood on their uniforms.

The U.S. military in Iraq released a statement with only the barest outline of the case, saying Maj.-Gen. James Thurman, commander of coalition troops in Baghdad, had ordered a criminal investigation into the alleged killing of a family of four in Mahmoudiyah, south of the Iraqi capital.

The Associated Press reported that one of the accused had already confessed and is being held in Baghdad, three others have surrendered their weapons and a fifth has been discharged from the military — apparently unrelated to this case — and has returned to the United States.

The military was already reeling from a probe of an alleged massacre of two dozen Iraqi civilians by U.S. Marines last November.

It is alleged the Marines sought revenge for the killing of a colleague and at least four are being probed, but no one has been formally charged.

Since then:

# Four army soldiers were charged with premeditated murder in the slaying of three Iraqi detainees in May, then threatening to kill another soldier if he reported the shootings.

# Seven Marines and a naval corpsman were charged with murder and kidnapping in the April killing of a disabled Baghdad man.

They are alleged to have planted a rifle and shovel near the body of the man in a bid to make it appear he was planting a roadside bomb.

# In another incident, two Pennsylvania National Guardsmen were charged with involuntary manslaughter in relation to a February killing of an unarmed Iraqi man.

Additional articles by Tim Harper

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