SEOUL, South Korea - North Korea loaded booster rockets onto a launch pad and moved about 10 fuel tanks to a launch site in preparation to test-fire a long-range missile that could reach as far as the U.S. mainland, a newspaper reported Saturday. South Korea and the United States made the assessment after analyzing satellite images, the Chosun Ilbo reported, citing an unnamed high-level South Korean government official. On Friday, a U.S. government official said Pyongyang was accelerating preparations for testing the missile.