PINEVILLE, La. — A Louisiana soldiers was killed in Iraq when a roadside bomb blew up the heavily armored Bradley Fighting Vehicle he was traveling — just four days after a similar attack killed six from Louisiana.

Killed Monday was Sgt. Robert Sweeney III of Pineville, family members said. Also killed was Staff Sgt. Bill Manuel of Oberlin.

Both were members of the Louisiana National Guard’s 256th Infantry Brigade.

American officials said that in addition to the two soldiers who were killed, four were wounded in the attack.

“I extend my deepest sympathies to the families and loved ones of our fallen heroes and to the entire 256th family,” Gov. Kathleen Blanco said in a news release.

“To those soldiers who are wounded, I pray that God will restore your health and give you great comfort.”

A spokesman for the National Guard said official...