Kim Jong Un

North Korea's Kim praises submarine launch test as a success

North Korean leader Kim Jong Un said Thursday that his country had achieved the "success of all successes" in launching a missile from a submarine, saying it effectively gave the country a fully equipped nuclear attack capability and put the U.S. mainland within striking distance.

Kim's comments, carried by Pyongyang's official Korean Central News Agency, came a day after South Korean officials said a ballistic missile fired from a North Korean submarine was tracked flying about 500 kilometers (310 miles), the longest distance achieved by the North for such a weapon.

North Korea already has a variety of land-based missiles that can hit South Korea and Japan,...