BAQOUBA, Iraq, AP – Gunmen opened fire on a minibus carrying Iraqi workers to a U.S. airbase in central Iraq, killing 13, police said Tuesday.

Police Col. Mahdi Saleh, from the Khalis police force, said 13 people were killed when assailants in two cars attacked the bus on its way to al-Faris airbase in Baqouba, 35 miles northeast of Baghdad.

Another police official, who declined to give his name, said 10 workers were killed. The bus driver slammed into a nearby car, killing three civilians inside, he said.

In a separate account, Dr. Ahmed Fouad, head of Baqouba hospital morgue, said the morgue had received seven bodies, and that there were six others injured.