Less than an hour earlier and a little farther south, a parked minibus blew up near a police checkpoint in the city of Baquoba. The blast killed three passers-by and wounded 29 others, said local council spokeswoman Samira al-Shibli.
The blasts followed a wave of violence across Iraq on Monday during which 115 people were killed. Many of those attacks also targeted security forces. Al-Qaida's new leader Abu Bakr al-Baghdadi announced days before that the network would stage attacks and try to rebuild tribal alliances to make a comeback in Sunni areas from which it had retreated in 2007-2008.
Iraq's Shiite-led government has been under intense pressure to prove it can protect the country from terrorism after years of similar violence and, on Tuesday, continued its trial of the Sunni vice president who is accused of running death squads against security forces and religious pilgrims.
But the case has also deepened the rift between Iraq's political factions, which break down largely on sectarian lines.
Witnesses testified during the court hearing about weapons taken from the homes of Vice President Tariq al-Hashemi and Ahmed Qahtan, his son-in-law and office manager.
Al-Hashemi, who is in Turkey avoiding trial, has denied the wrongdoing and has said he is the victim of a political vendetta by Shiite Prime Minister Nouri al-Maliki. He is one of Iraq's highest-ranking Sunni politicians.
Al-Hashemi's defense lawyers also announced that an Iraqi appeals court refused to allow President Jalal Talabani to testify in the trial
In May, al-Hashemi filed a request to have Talabani, an ethnic Kurd, serve as a character witness, along with two other government officials and five Sunni lawmakers. Defense lawyers sought to ask if they had any information about al-Hashemi's role in terror attacks.
But the three-judge panel rejected the request, saying it would add nothing to the case. Attorney Muayad Obeid al-Ezzi, the head of al-Hashemi's defense team, announced the decision to reporters, noting that Iraq's federal appeals court was upholding an earlier decision by the Baghdad's criminal court to not take Talabani's testimony.
The trial is scheduled to continue Aug. 14.