Eight civilians have been killed in an air strike by US military helicopters north of Baghdad, Iraqi police say.
Two children were among those who died in the attack on Wednesday evening near the town of Baiji, the police said.
Baiji's police chief said the attack targeted a group of shepherds in a farming area. The US military said the incident was under investigation.
In other violence, an Iraqi TV cameraman is reported to have been shot dead in crossfire in Baghdad.
A US military spokeswoman, Lt Col Maura Gillen, said one of its helicopters fired in the Baiji area after noting "suspicious activity", and she said people travelling in a car had ignored warnings to stop their vehicle.
Locals said some of those killed had been people running away on foot after the US forces entered the area.
A local man, Ghafil Rashed, told Reuters that his brother and son had been killed in the attack: "The Americans raided our houses... People started fleeing with their children, then the aircraft started bombing people in a street along the farm."
Baiji's police chief, Col Mudher Qaisi, told Reuters news agency that the attack was a criminal act, and would make relations between Iraqi citizens and the US forces tense.
"This will negatively affect security improvements," he said.
In a press statement, the US military said it regretted the loss of innocent civilian lives.
In a separate development the Iraqi satellite television channel, Afaq TV, said one of its cameramen, Wissam Ali Auda, had been shot dead in sniper fire in the Obeidi district of Baghdad.