South Korea fires warning shots at North Korean patrol boat for sea intrusion.

South Korea fired warning shots at a North Korean vessel that crossed the maritime border, raising tensions over the North's missile tests. The North's incursion came as tension flared over the North's stepped up military activities in recent weeks, including Friday's test of a new solid-fuel intercontinental ballistic missile. Pyongyang threatened military action as South Korea and U.S. forces have been carrying out their annual springtime exercises since March, calling them a rehearsal for nuclear war.