Four U.S. soldiers killed in Iraq

BAGHDAD (Reuters) - Four U.S. soldiers were killed on Monday in Iraq, the military said on Tuesday.

It said in a statement that three soldiers died of wounds sustained from an explosion in Iraq's northern province of Nineveh. In another statement, the military said a U.S. soldier was killed in Baghdad during combat operation.

No other details of the incidents were available.

U.S. and Iraqi forces launched on Monday an offensive across the country against al Qaeda and "Iranian-supported" Shi'ite militants in an apparent attempt to thwart an expected surge in violence.