Gunmen shot down an Iraqi army helicopter during clashes in the central Salah al-Din province Wednesday, killing four soldiers, security officials said, dpa reported.
Three gunmen were also killed in the fighting near the city of Baiji, 220 kilometres north of Baghdad, the officials said.
The incident comes a day after the United Nations released figures showing that 979 Iraqis were killed in September, making it one of the deadliest months of the last five years.
Car bombings and other attacks, often targeting Sunni and Shiite places of worship, have raised fears of a return to the sectarian violence that pushed the country to the brink of civil war in 2006-07.