PIPELINE EXPLOSION KILLS 103: A spark from subway construction set off a natural gas explosion this morning in the South Korean city of Taegu. At least 103 people were killed, 60 of them teen-aged students. 200 others were injured. Critics of the government gas monopoly say the government has expanded its network of pipes too quickly, at the expense of safety. South Korean President Kim Young-sam said the explosion was a result of "carelessness."