The bombing took place in Dibis district of Kirkuk province while a police convoy was travelling on a main street, according to a former spokesperson for Tuz Khurmatu mayor.
At least three federal policemen were wounded, BasNews repored.
No groups or organisations have yet claimed responsibility for the attack, but the Islamic State (IS), who has recently stepped up its terrorist attacks across the region, is suspected.
Reporter's code: 50101