A ballistic missile launched from North Korea flew about 500km, South Korea's military says.
The missile launched early on Sunday was North Korea's "show of force" against the hard-line stance of the administration of US President Donald Trump on Pyongyang, South Korea's Office of Joint Chiefs of Staff said in a statement.
"The flight distance was about 500km and South Korea and the United States are conducting a close-up analysis on additional information," the statement said.
South Korea's presidential office said it has called a national security meeting.
The US military said detected the missile test and is assessing the launch.
"We can confirm that we did detect a missile launch from North Korea," a US defence official said, speaking on condition of anonymity.
"We are assessing and will have more information soon."