A 21-year-old man scaled a 10-foot-high fence on the observation deck of the Empires State Building last evening and thudded to the ground 86 floors below in front of horrified onlookers. "It was an explosion," a witness told the New York Daily News. "His body was shattered and his sneakers were scattered on the sidewalk." One pedestrian ran to cover the body with an umbrella. The jumper has not yet been identified. Some 30 people have leaped to their death from the landmark since it was built in 1931.