South Korea stated that North Korea launched a ballistic missile off its eastern coast on Sunday. The Japanese Coast Guard reported that a projectile, believed to be the North Korean missile, has already fallen, adding that it may be a ballistic missile. Japan's NHK broadcasting agency indicated that the missile appears to have fallen outside Japan's exclusive economic zone. Tensions on the Korean Peninsula have escalated since Pyongyang launched its first military reconnaissance satellite in November. In December, North Korea reported that it tested its latest intercontinental ballistic missiles to measure the wartime readiness of its nuclear forces in response to increasing U.S. hostility, while Washington and its allies implemented a system for immediate missile data exchange.