South Korea's Joint Chiefs of Staff (JCS) said the two medium-range missiles flew about 500 kms.
Japan's Vice Defence Minister Toshiro Ino said the missiles seemed to have landed outside Japan's exclusive economic zone (EEZ) and there had been no report of damages.
"North Korea's ballistic missiles were launched at steep angles and landed in the East Sea," South Korea's JCS said in a statement.
"South Korean and the United States intelligence authorities are conducting a thorough analysis, factoring recent trends related to North Korea's missile development."
South Korea convened a National Security Council (NSC) meeting over North Korea's missile launch and "strongly condemned" for escalating tensions on the Korean Peninsula, South Korea's presidential office said in a statement.
The presidential office added that the North's continued provocations and development of nuclear weapons and missiles would further endanger the North Korean regime.
More about: