The US military has detained 371 people in Iraq as part of Operation Desert Scorpion, aimed at rooting out armed resistance, according to the American military.
Thirty-six raids took place in Tikrit and Kirkuk in the north, where 215 people were held. The remainder were detained in 11 raids in central Baghdad.
Heavy firearms, including 18 rocket-propelled grenades, and more than 120 rifles, pistols and machine guns were seized.
Operation Desert Scorpion is an operation designed to isolate and defeat remaining pockets of resistance which the US says are "seeking to delay the transition to a peaceful and stable Iraq".
Central Command announced the death of another US soldier in an "apparent non-hostile incident" in the Taji area, just north of Baghdad.
It takes to 49 the number of American soldiers killed in attacks or accidents since President Bush declared the war in Iraq effectively over on May 1.