BAGHDAD, Iraq (CNN) -- Iraqi and U.S. troops raided several Shiite neighborhoods in Baghdad on Friday, detaining hundreds and uncovering a large cache of weapons and explosives, an Iraq Defense Ministry official said.
Several hundred Iraqi soldiers backed by U.S. forces moved into neighborhoods in southwest and northwest Baghdad on Friday morning, the official said.
Security forces detained 123 suspects in the southwest Baghdad operations, and another 12 were taken into custody in the northwest region.
Four of those detained in northwest Baghdad were captured in al-Rahma Shiite mosque. Three unidentified bodies were also found in the mosque, according to the Iraqi official.
The munitions cache, which included components for roadside bombs, was found near the office of radical Shiite cleric Muqtada al-Sadr, the leader of the Mehdi Army militia, according to a U.S. military spokesman.
Some people were tested on the scene for explosive and gunpowder residue, according to Lt. Col. Steve Stover.
He said 223 light and medium weapons and 30 kilos (66 pounds) of C4 explosives were found in one raid.
Elsewhere in Iraq, a roadside bomb killed a civilian interpreter and wounded seven U.S. Marines and two Iraqi police officers in Falluja on Friday morning, according to the U.S. military.
The Iraqi Interior Ministry had called the attack a suicide car bombing and said that an Iraqi police officer was killed.
An Interior Ministry official said the bombing occurred at a checkpoint normally manned by Iraqi police and U.S. troops.
Also in Falluja on Friday, a suicide bombing outside police headquarters wounded officers, the official said.
Falluja had been a stronghold for insurgents in the early days of the Iraqi war but is now a center for the "awakening," which opposes al Qaeda in Iraq.
U.S. and Iraqi military operations have chased many al Qaeda in Iraq cells out of Anbar province. Those militants now predominate in other areas, such as Nineveh province, and security forces have launched an offensive against them there.