The Democratic People's Republic of Korea (DPRK) fired one projectile, believed to be a short-range missile, into the eastern waters, South Korea's Joint Chiefs of Staff (JCS) said Tuesday.
The JCS said in a statement that the projectile was launched eastwards from the DPRK's inland region at 6:40 a.m. local time (2140 GMT Monday).
It did not specify if the projectile is a ballistic missile. But the Japanese government said it appears to be a ballistic missile and splashed into waters outside its exclusive economic zone, according to Japan's Kyodo News.
The intelligence authorities of South Korea and the United States were making a precision analysis on further details of the launch.
The JCS said the South Korean military was closely monitoring relevant situations and maintaining a full readiness posture in cooperation with the United States to brace for the DPRK's possible further launch.
It came after the DPRK test-fired two short-range ballistic missiles into eastern waters on Sept. 15.