A Canadian tour company canceled planned cruises to Cuba because of threats of violence and a bomb scare. The inaugural cruise was scheduled to stop in Havana Nov. 18, but was put on indefinite hold because the company could not guarantee the safety of its passengers and crew. More than 400 Americans were booked for the trip, which the company believes does not violate the U.S. ban on travel to Cuba. Anti-Castro Cuban exiles were blamed for the threats.