A US military helicopter air strike on a car last night killed eight civilians, including two young boys, in Baiji north of Baghdad.
Baiji's police chief Colonel Mudhher al-Qaisi said the civilians were shepherds who were in a farming area in the town when the strike took place.
"This is a criminal act. It will make the relations between Iraqi citizens and the US forces tense. This will negatively affect security improvements," said al- Qaisi.
"There were two boys, one was eight and the other was 11," said police major Ahmed Hussein.
A US military spokeswoman, Lt-Col Maura Gillen, said the US military was following up the incident, claiming "suspicious activity" had been noted and warnings to stop the car were ignored.
The incident comes at a sensitive time just after senior government officials expressed outrage after reports this month that a US.soldier had used a copy of the Koran, the Muslim holy book, for target practice. The soldier was disciplined and removed from Iraq.