All officials spoke on condition of anonymity as they were not authorized to release information to journalists.
The attacks came a day after a series of coordinated explosions hit mainly Shiite commercial areas in Baghdad and outside the capital, killing at least 35 people and wounding 120.
Last Thursday, a suicide bomber struck a group of Shiites gathered in Sadiyah to commemorate the 7th century death of a revered Shiite shrine. That attack killed at least 32 people and wounded 75.
There was no immediate claim of responsibility for the attacks, but suicide attacks and large-scale bombings — especially against security forces or crowded markets in Shiite areas — are a favorite tactic of al-Qaida's local branch and Sunni insurgents. The Sunni extremists launch such attacks as they view Shiites as heretics.
Violence in Iraq in the past eight months has killed more than 5,500, according to the United Nations. Thursday's explosion brings the death toll across the country this month to 292, according to an Associated Press count.