Elsewhere in the volatile Diyala province, a roadside bomb killed five members of a family, bringing the day's casualty toll to 30. Diyala, a stronghold of Sunni insurgents and the al Qaeda in Iraq terror network, has been the site of much of the recent violence, with an ebb in attacks elsewhere in the country.
In the Diyala town of Jalula, the assailant drove a car Tuesday toward a building where recruits for a new police emergency response unit had assembled, said Col. Ahmed Mahmoud Khalifa, the local police chief. The U.S. military said five of the dead were police, the remainder civilians.
Police guard Falah Hassan, 28, who stood at the gate of the compound, said a thunderous explosion went off about 100 yards away.
"I saw burned bodies, wounded people and small pools of blood," said Hassan, speaking from a hospital bed in the northern town of Sulaimaniyah where some of the 40 wounded had been taken.
Yasir Ramadan, 21, one of the recruits, said about 30 people were standing near the gate when the car blew up. He said he was injured by shrapnel, and would require eye surgery.
"Today I was so happy to get a job at last to feed my wife and two kids," said Ramadan, who was also hospitalized in Sulaimaniyah.
"I used to work as day laborer in construction, but there's no construction in the area, and it's hard to find work," he said, adding that despite the trauma, he'd join the police.
Another recruit, Yasir al-Dulaimi, 18, also said he wouldn't be deterred, despite injuries to his head and right arm. "We will beat terrorism and al Qaeda. We will not abandon our work," he said. "If we do so, we will abandon our honor as well because al Qaeda would take full control over our area."
Jalula is an ethnically mixed town of 67,000 residents, with 70 percent Sunnis, 25 percent Kurds and five percent Shiites, Khalifa said. Unemployment runs high in the impoverished community.
Khalifa said tribal sheiks had been asked to send recruits to the new police unit. Monday was the last day of recruitment, and applicants came to the police center on Tuesday to check whether they had been accepted, he said.
Insurgents across Iraq have repeatedly targeted police stations, including recruiting posts, to disrupt U.S.-led efforts to gradually hand control to Iraqi forces.
After the blast, security forces imposed a curfew on Jalula, about 80 miles northeast of Baghdad.
Elsewhere in Diyala, a roadside bomb struck a van carrying a Sunni family near the town of Mandali along the Iranian border, said Col. Sarchal Abdul-Karim, a spokesman of Iraqi border guards in the area.
Five members of the family were killed, including two women and two children, the spokesman said. The family was on the way to a religious shrine, the colonel added.
Also Tuesday, a bomb planted in a parked car blew up in the city of Tikrit, north of Baghdad. A police official initially said four people were killed. However, another police official later said he only received word of wounded, and security officials at a local hospital said they knew of 12 people injured in the blast.
Tikrit is Saddam Hussein's hometown and has been a hotbed of the Sunni insurgency since the 2003 ouster of the late Iraqi leader. But it has enjoyed relative quiet since violence levels significantly dropped over the past year in much of Iraq.
In other developments: