A former US soldier has appeared in a US federal court, charged with the rape and murder of an Iraqi woman, and the killing of three members of her family.
Four soldiers are alleged to have plotted to carry out the attack
Steven Green, 21, is accused of carrying out the rape and murders in Mahmoudiya, south of Baghdad, in March, along with other soldiers.
A military inquiry into the incident is the latest in a series into alleged abuses by US troops in Iraq.
Mr Green was arrested by FBI agents on Friday in North Carolina.
He faces a possible death penalty if convicted.
A statement from the US attorney in Kentucky says Mr Green is charged with going to a house near Mahmoudiya with three other people to rape a woman living in the house.
He allegedly shot and killed a man, a woman and a five-year-old girl and after raping another woman, he is alleged to have shot and killed her, the statement said.
According to an affidavit based on interviews with soldiers from his unit, Mr Green took the family into a bedroom, from where shots were heard.
"Green came to the bedroom door and told everyone, 'I just killed them. All are dead," the statement says.
Another affidavit said Mr Green, who belonged to the 101st Airborne Division, had been discharged from the army "due to a personality disorder" before the rape and killings were known about.
Some of the suspects belong to the Division's 502nd Infantry Regiment, the same unit as two soldiers kidnapped, tortured and killed by insurgents south of Baghdad last month.
Some reports suggested that this event may have spurred soldiers to come forward with information about the killings.
Mr Green is due to appear in court at a detention hearing in Charlotte, North Carolina, on 10 July.