South Korea's military said the North launched projectiles on Monday that appear to be ballistic missiles.
The Joint Chiefs of Staff said the two projectiles were detected at 8:50 AM and 8:54 AM.
"This morning, our military detected two projectiles that appear to be short-range ballistic missiles, fired eastward to the East Sea from Sunan airfield in Pyeongyang."
The military said the suspected ballistic missiles traveled about 380 kilometers and reached an altitude of 42 kilometers.
They reportedly flew at a speed of about five times the speed of sound.
An official from the Joint Chiefs of Staff said this appears to have been made to test the North's capability to consecutively launch missiles, with increased accuracy.
Seoul's military said that it is closely monitoring the situation, to be ready for any additional launches by the North, and said South Korea and U.S. intelligence agencies are analyzing the latest move.
The place where Monday's projectile was launched, Sunan airfield in Pyeongyang is where the North had previously test-fired several of its weapons, including the Hwasong-12, an intermediate-range ballistic missile in 2017.
An expert says testing weapons from the capital city of Pyeongyang indicates a message to both the North Korean people and to the outside world.
"North Korea is having trouble with not only the pandemic, but also with sanctions and closed borders. So by firing a missile from Pyeongyang, it aims to boost its internal solidarity within the North Korean people. It's also sending a message to the outside world that it will not be affected by sanctions, through continuously firing missiles."
This is the fourth launch this month, taking place just three days after the North fired suspected short-range ballistic missiles last Friday.
The North reported that they were ballistic missiles launched from a train, marking the North's second known launch using a railway platform, following the first one last September.
The North also launched missiles last Tuesday and on January 5th, and claimed that both of those launches were successful tests of its "hypersonic" missiles.
Hypersonic missiles are seen as a game-changer because they are easier to maneuver and operate at high speeds meaning they are harder to track and intercept.
Last Tuesday's launch was conducted under the watch of the North's leader Kim Jong-un.
Pyeongyang is banned from developing or testing ballistic missiles and nuclear weapons under multiple UN Security Council resolutions.
Bae Eun-ji, Arirang News.