Military spokesman Lt. Col. Lee Packnett in Baghdad told CBSNews.com that the roadside blast also left three Iraqi troops and an interpreter dead.
A rocket-propelled grenade struck a vehicle in northern Baghdad Thursday afternoon, killing one soldier and wounding three others, another statement said.
On Wednesday, four U.S. soldiers were killed when their convoy was struck by a roadside bomb in western Baghdad, according to Packnett.
Southwest of Baghdad, two Task Force Marne soldiers were killed and four were wounded Wednesday when explosions struck near their vehicle, according to a statement issued earlier Thursday.
Two Marines assigned to Multi-National Force — West also were killed Wednesday while conducting combat operations in Anbar province, west of Baghdad, Packnett said.
None of the troops names were immediately released, pending family notification.
The deaths raised to at least 3,545 members of the U.S. military who have died since the Iraq war started in March 2003, according to an Associated Press count.
Meanwhile, a U.S. air strike aimed at a booby-trapped house in Baqouba missed its target and "accidentally hit" another structure, wounding 11 civilians, the military said, adding the incident was under investigation.
U.S. troops had cleared the area to destroy a house containing explosives believed placed by al Qaeda, but "the bomb missed its intended target and struck another structure," the military said. "Reports indicate that 11 civilians were injured."
The initial target was later destroyed by a Hellfire missile, producing a large secondary explosion, according to the statement.
A spokesman for the 1920s Revolution Brigades, a nationalist Sunni insurgent group that has begun cooperating with U.S. and Iraqi forces in the fight against al Qaeda in Diyala, said the air strike mistakenly struck a building being used as a headquarters by the group. The spokesman, who declined to be identified due to security concerns, said two members were killed and four were wounded.
Hospital officials said ambulances were bringing dozens of bodies of militants who have been killed from the western half of the city, which was under a strict curfew.
Ten thousand U.S. and Iraqi troops are trying to wipe out an al Qaeda stronghold in Baqouba, reports CBS News national security correspondent David Martin.
But Lt. Gen. Ray Odierno, the ground force commander, visited the city Thursday and said most of al Qaeda's senior leaders managed to escape, leaving behind a maze of deadly booby traps, adds Martin.
The latest military report on the Baqouba offensive said U.S.-led forces had killed 41 insurgents, discovered five weapons caches and destroyed 25 bombs and five booby-trapped houses.
In other developments:
Maj. Gen. Abdul Karim al-Rubaie of the Iraqi army in Diyala, said that overall the offensive that began Monday in Diyala was going well and operations were focused Thursday on the areas of Jurf al-Milih and the northern part of the Baqouba market, which has been the site of several execution-style killings by al Qaeda in recent weeks.