(Adds quote, background) BAGHDAD, Jan 16 (Reuters) - Four U.S. soldiers were killed by a bomb in northern Iraq on Monday, the military said in a statement on Tuesday. "Four Task Force Lightning Soldiers assigned to the 4th Brigade, 1st Cavalry Division were killed Monday as a result of an improvised explosive device while conducting operations in Nineveh province," it said, giving no other details. Nineveh province includes the city of Mosul, Iraq's third largest, and the town of Tal Afar. More than 3,000 Americans have died since the invasion of Iraq four years ago. U.S. President George W. Bush is sending about 20,000 more troops, despite opposition in Congress, to add to the roughly 130,000 already in Iraq, in an effort to stifle sectarian violence principally in the capital, Baghdad.
