North fires ballistic missile
The missile is believed to be a Scud type, according to the Joint Chiefs of Staff (JCS).
It was launched eastward from the vicinity of Wonsan, Gangwon Province, at around 5:39 a.m., it said, adding South Korea and the United States are analyzing more information.
"Our military is keeping a close watch on the possibility of an additional provocation by North Korea and is maintaining full preparedness," the JCS said.
The North's latest action was immediately reported to President Moon Jae-in, who ordered related government officials to convene a National Security Council meeting.
The session started at 7:30 a.m., presided over by Moon's national security adviser Chung Eui-yong.
It marked the communist nation's ninth missile test this year and the third since the launch of the Moon administration, which is seeking to reach out to the communist neighbor.
The North fired a mid-range missile, known as the Pukguksong-2, on May 21 and conducted a KN-06 surface-to-air guided missile test Saturday.
U.S. President Donald Trump was also briefed on the North's provocation, a White House official said.
The Japanese government strongly denounced the North as the missile appears to have landed in waters near its territory.
"This ballistic missile launch by North Korea is highly problematic from the perspective of the safety of shipping and air traffic, and is a clear violation of United Nations Security Council resolutions," Chief Cabinet Secretary Yoshihide Suga said.