BAGHDAD, May 21 (Xinhua) -- The U.S. military said on Thursday that three of its soldiers were killed in a bomb attack in southern Baghdad.

    "Three Multi-national Division-Baghdad soldiers died when an improvised explosive device detonated near their patrol in Baghdad at approximately 10:40 a.m. (0740 GMT) on May 21," a military statement said.

    It said the incident is under investigation.

    Earlier in the day, an Iraqi police source said that three U.S. soldiers were killed and five others wounded when a suicide bomber blew himself near a U.S. patrol at the entrance of a marketplace in Baghdad's Doura district.

    The attack also killed 12 civilians and wounded 25 others in the popular market of Athoriyin, the source said.

    The military statement did not say whether the roadside bombing is the same of Doura suicide attack reported by the Iraqi police earlier.

    About 4,299 U.S. soldiers have been killed in Iraq since the breakout of the Iraqi war in 2003, according to media count based on Pentagon figures.

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