Police officials say attackers sprayed with bullets a group of troops manning a checkpoint early today near the city of Mosul, 360 kilometres northwest of Baghdad.
Medics confirmed the casualties. All officials spoke anonymously because they were not authorised to talk to the media.
Members of Iraq security forces have been a favourite target for Sunni insurgents who want to undermine the Shiite-led government in Baghdad. Violence has escalated in Iraq over the past year, with 2013 seeing the country's highest death toll since the worst of the country's sectarian bloodletting began to subside in 2007.