Nuclear-armed North Korea fired what appeared to be two short-range ballistic missiles into the sea off its east coast, South Korea's military said on Thursday, in what would be the sixth round of missile tests this month.

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 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...