South Korea’s military says it has detected that North Korea fired a short-range ballistic missile toward waters off its western coast. The South’s Joint Chiefs of Staff says the weapon was fired from an area around the western coastal city of Nampo. It did not immediately release an assessment on how far the missile flew. The launch came after the influential sister of North Korean leader Kim Jong Un warned Tuesday that her country is ready to take “quick, overwhelming action” against the United States and South Korea as the allies expand their military training to cope with a growing North Korean nuclear threat.