The latest attack follows an incident last Thursday, when armed men killed 16 soldiers and planted al-Qaeda's flat nearby.
The attacks in Azamiyah and Mansour districts were likely to raise concerns that
armed groups are taking advantage of the enduring political vacuum nearly five months after Iraq's parliamentary elections failed to produce a clear winner.
Politicians are still bickering over the formation of a new government, with the main hurdle being who should become the next prime minister.
Figures compiled by the ministries of health, interior and defence showed July to be the deadliest month in Iraq in two years, with 535 people being killed in violence.
Security has vastly improved in Iraq but armed groups still launch attacks, frequently targeting the Iraqi army and police.