Iraqi officials say gunmen opened fire on the car of a colonel in the civil defense forces, killing him and his wife and wounding their three children.
The drive-by shooting in western Baghdad was one of three deadly attacks Friday.
In another ambush of a car in the capital, assailants killed an aide to Qusai al-Suhail, the deputy speaker of parliament.
Elsewhere, an Iraqi soldier was killed and four were wounded by a roadside bomb in Bala Ruz, 70 kilometers (45 miles) northeast of Baghdad.
The officials spoke on condition of anonymity because they were not authorized to talk to reporters.
Violence has ebbed in Iraq, but insurgents carry out frequent attacks on security forces and officials in an attempt to undermine the Shiite-led government.