Four people were killed Friday in a bomb blast that targeted a police patrol in the northern Iraqi city of Mosul, the head of the city's security forces said dpa reported
The bomb went off in western Mosul, killing two policemen and two civilians, Brigadier Mohamed al-Jabouri told dpa.
Three civilians were also injured.
Iraq has been shaken by a wave of attacks since the last US troops were withdrawn from the country at the end of last year.
On Thursday, 60 people were killed in a series of bombings in Iraq.
In the capital, Baghdad, tight security was imposed ahead of a major military parade by the Iraqi Army to mark its 91st anniversary.