It is among the most missiles ever launched by North Korea in a month, analysts said, as Pyongyang has kicked off 2022 by displaying a dizzying array of new and operational weapons.
South Korea's Joint Chiefs of Staff said it had detected the launch of what it presumed were two ballistic missiles about 8am local time on Thursday from near Hamhung, on the east coast of North Korea. They travelled for about 190km to a maximum altitude of 20km, JCS added.
The suspected missiles appeared to have landed outside of Japan's exclusive economic zone, Japanese Defence Minister Nobuo Kishi told reporters.
Japanese Prime Minister Fumio Kishida said the government was still gathering details on the launches, but that any tests of ballistic missiles are "deeply regrettable" and violate United Nations Security Council resolutions.
North Korea this month said it would bolster its defences against the United States and consider resuming "all temporally-suspended activities", an apparent reference to a self-imposed moratorium on tests of nuclear weapons and long-range missiles.
On Tuesday, North Korea fired two cruise missiles into the sea off its east coast, South Korea's military said, amid rising tension over a recent series of weapons tests.
Earlier in the month it tested tactical guided missiles, two "hypersonic missiles" capable of high speed and manoeuvring after lift-off, and a railway-borne missile system.
The series of missile tests has drawn condemnation from governments in the US and Japan and sparked meetings of the United Nations Security Council, which has sanctioned North Korea for violating resolutions that ban ballistic missile tests.
US President Joe Biden's administration sanctioned several North Korean and Russian individuals and entities this month on accusations they were helping North Korea's weapons programs, but China and Russia delayed a US bid to impose UN sanctions on five North Koreans.
North Korea has defended its missile tests as its sovereign right for self defence, and said the US sanctions proved that even as Washington proposes talks, it maintains a "hostile" policy toward Pyongyang.
North Korea has not launched long-range intercontinental ballistic missiles (ICBMs) or tested nuclear weapons since 2017, but began testing a slew of shorter-range missiles after denuclearisation talks stalled following a failed summit with the US in 2019.
