A roadside bomb exploded near the car of a senior Iraqi Finance Ministry (search) official Thursday, slightly wounding him but killing his guard and driver, police and hospital officials said.

The bomb exploded at about 8 a.m. near Yarmouk Hospital (search) in central Baghdad, said Col. Adnan Hussein, head of the Interior Ministry's information office. Ehsan Karim, the head of the ministry's audit board, was driving by on his way to the office.

Karim's guard and driver were killed, said Karima Ali Salam, a nurse at the hospital. Four bystanders were also injured.

Firefighters responding to the area fired their weapons into the air to disperse the crowds, initial U.S. military reports said.