FALLUJAH, Iraq, Jan. 11 (Xinhuanet) -- Insurgents detonated a roadside bomb near a U.S. military patrol in the flashpoint city of Fallujah on Wednesday, killing three U.S. soldiers and wounding another, one witness said.

    "A roadside bomb went off in al-Dhubat district as a U.S.patrol passed by, destroying a U.S. Humvee as well as killing three soldiers aboard and wounding another," the witness told Xinhua on condition of anonymity.

    Earlier in the day, U.S. forces asked Iraqi soldiers to replace local police to take charge of checkpoints around the city, as U.S.troops prevented movement of local residents from a district to another, witnesses said.

    U.S. troops are apparently preparing for a military action as insurgents intensify attacks against U.S. and Iraqi forces.

    The Sunni-dominated Fallujah, some 50 km west of Baghdad, has witnessed sporadic attacks against U.S. and Iraqi forces despite U.S.-Iraqi military operations in the city to stamp out insurgency.   Enditem