"North Korea fired an unidentified missile at around 5:27 a.m. today from an area in the vicinity of Kusong, North Pyongan Province," the Joint Chiefs of Staff (JCS) said in a statement, Yonhap reported.
The projectile flew some 700 kilometers, it said, adding it's analyzing more details.
The flight distance suggests a success of the missile test, the North's first military provocation since the inauguration of Moon last week.
Read alsoNorth Korea fails in missile testThe Japanese government also announced that the North's missile flew for half an hour and landed in waters between the Korean Peninsula and Japan.
Moon is presiding over the NSC session that started at 7 a.m., according to his office Cheong Wa Dae.
The JCS said, "Our military is maintaining a full defense posture, closely monitoring the North Korean military's move."
The North test-fired a Pukguksong-2 intermediate-range ballistic missile (IRBM), also known as KN-15, from the same site on Feb. 12.
Sunday's launch was the North's first-known missile test in two weeks.
