Insurgents shot down an American military helicopter near Falluja on Friday, killing one crewman, and angry protesters gathered outside one of Baghdad’s principal Sunni Muslim mosques to protest a raid in which American troops arrested a prominent Sunni cleric and 31 others, as well as seizing what they described as a large cache of weapons and bomb-making equipment. The attack on the helicopter near Falluja, the city 35 miles west of Baghdad that has been the scene of relentless violence against the Americans, was the first time insurgents had succeeded in destroying a helicopter since a rash of downings in November. Those attacks destroyed four helicopters and killed more than 40 soldiers, contributing to a death toll that month of 81. The downed helicopter was an OH-58 Kiowa Warrior, a small, highly maneuverable machine prized by its crews as a sort of aerial motorcycle. It is the first time enemy fire has brought down what the Army has come to regard as its helicopter of choice in Iraq. Full Story