AN EXPLOSION ripped through a tavern in Waterloo, Iowa, Monday, killing five people, injuring two others and leveling the building, police said. . . . A JAPANESE newspaper helicopter crashed Tuesday, killing all three people on board, after apparently bumping into the chopper of a rival paper, authorities and witnesses said. . . . GUNMEN TOOK religious, political and ethnic feuds to the streets of Pakistan's largest city of Karachi, killing at least 20 people in two days of widespread lawlessness, police said Tuesday.