They are the first American casualties since the military completed the withdrawal of combat forces from Iraqi cities June 30.

    Baghdad - Three American soldiers in Iraq were killed Thursday evening when three rockets or mortar shells hit their base outside the southern city of Basra, the U.S. military said today.

    They were the first American casualties since the military completed the withdrawal of combat forces from Iraqi cities June 30 and the attack was in an area considered one of the country's calmest.

    There has been no significant upsurge of violence since the pullback, but militants have continued to stage small-scale attacks, mainly in Baghdad and the northern city of Mosul.

    Two pilgrims, a man and his wife, were killed in a bombing today in southeast Baghdad as hundreds of thousands of Shiite Muslims converged from all over Iraq on a shrine to commemorate the anniversary of the death of an 8th century holy figure, Imam Musa Khadim.

    Such pilgrimages are typically targeted by Sunni extremists, and security has been tightened across the city to safeguard the route that the pilgrims take to the shrine in the northwestern district of Kadhimiya.

    Two other bombings injured 13 people, but there have been no major attacks of the kind that often occurs during such events.

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    Times staff writer Raheem Salman contributed to this report.