Damascus, Ark. — A flatbed truck hauled away the nine-megaton nuclear warhead Monday which was flung 200 yards from a Titan II missile that exploded Friday, killing one airman and injuring 21 others. An eight-vehicle convoy, including the truck carrying two lead containers marked "Do Not Drop," arrived safely at Little Rock Air Force Base, about 60 miles from the site. One Air Force official at the scene, asked if the convoy contained the warhead, just smiled and gave a thumbs-up sign. Pentagon sources said the truck was indeed removing the warhead, which showed no damage except a slight dent. The Air Force would not officially confirm or deny the presence of a warhead.