The hermit state fired the missiles early on Wednesday local time (tonight UK time), according to Yonhap news agency, citing the South Korean military’s Joint Chiefs of Staff.
The projectiles were reportedly launched from the Hodo peninsula in South Hamgyong Province on North Korea’s east coast.
South Korea reportedly said it is monitoring the situation in case of additional launches and maintaining a readiness posture.
The White House, the Pentagon and the U.S. State Department did not immediately respond to requests for comment.
It comes just a week after North Korea test-fired two new short-range ballistic missiles.
One of the two was a new type that flew almost 435 miles before crashing into the sea.
The missiles were launched from Wonsan – a city on the eastern coast – as Kim Jong Un carried out his first test since he and US President Donald Trump met last month and agreed to revive denuclearisation talks.
Kim’s latest test now further threatens to derail talks after he and Trump met at the demilitarised zone (DMZ) between North and South Kiorea at the end of June.
In May, Kim already risked fury as he watched through binoculars, laughing and smiling, as North Korea test-fired two missiles.
Pyongyang’s state media said that drill was intended for the country’s western “frontline defenders” to demonstrate their ability to carry out “combat missions”.
Kim and Trump then met at the DMZ in June, and agreed to hold a new round of talks following two earlier summits in Singapore and Vietnam.
Only since then, North Korea has blasted the US and South Korea over their plans to stage another round of joint military drills.
Pyongyang considers the drills a preparation for invasion.
And its latest test suggests Kim’s hermit state shows no signs of following its promise to denuclearise any time soon