Special report: Tension escalates in Iraq

    BAGHDAD, May 11 (Xinhua) -- A roadside bomb went off near a convoy of sport utility vehicles (SUVs), usually used by foreign contractors, in northern the capital on Friday, an Interior Ministry source said.

    "An explosive charge detonated near a convoy of four-wheel-drive vehicles, guarded by U.S. Humvees, while passing in the Kadhumiyah neighborhood, burning one of the SUVs," the source told Xinhua on condition of anonymity.

    It was not clear whether there was any human casualty as the U.S. troops cordoned off the area preventing the Iraqi police from approaching the scene, the source said.

    Late on Thursday, another attack targeted U.S. troops when a car bomb parking near the Kahramanah Square in Baghdad's central district of Karradah detonated, the source added.

    The source could not give out the casualties of the U.S. patrol as the U.S. troops sealed off the area too. However, the U.S. military announced on early Friday three U.S. deaths in Thursday's insurgent attacks against the army across Iraq.

    According to separate military statements, a U.S. soldier was killed by an explosion during combat operations in Diyala province, north east of Baghdad, while the second soldier was killed by small-arms fire in combat security operations in south of the capital.

    A third soldier was killed when his patrol came under small-arms fire in Diwaniyah, some 180 km south of Baghdad, a statement said.

    About 3,385 U.S. soldiers have been killed in Iraq since the U.S.-led invasion broke out in 2003, according to media count based on Pentagon figures.