Five American men have been arrested by Iraqi police, the US embassy in Baghdad said on Sunday, reportedly in connection with an attack in which another American was killed.
An embassy spokesman said the men, who were neither diplomats nor military personnel, appeared to be well and that no formal charges had been pressed against them.
He gave no details on why the five had been arrested, and declined to specify if they worked for a private security contractor in Iraq.
Earlier on Sunday, CNN reported on its website that five contractors had been detained over the killing of 60-year-old James Kitterman, who was found stabbed to death in a car in the capital's high-security Green Zone on May 22.
Citing an Iraqi official it did not name, the American broadcaster said once the suspects have been charged and referred to trial, the case will be sent to the Central Criminal Court in Baghdad.
If such a step were taken, it would be the first time American citizens have faced trial in Iraq since jurisdiction was returned to Baghdad by the United States under an accord signed last November, the report added.