Citing South Korea's military, media reported the launch took place at about 4 a.m. local time.
No further details of the launch have yet been made public amid a pending analysis by both South Korean and US intel authorities, South Korea's Joint Chiefs of Staff (JCS) has indicated.
A message issued to media by the JCS reads: "While strengthening our monitoring and vigilance, our military is maintaining a full readiness posture in close cooperation with the United States."
The Saturday launch comes days after North Korea announced it carried out a tactical nuclear strike drill that simulated an attack on its southern neighbor, with officials specifying the "scorched earth strikes" focused on "major command centers and operational airfields."
At the time, North Korean authorities had also cited the recent Ulchi Freedom Shield joint drills between the US and South Korea for its own exercise. Officials commented that the military exercises proved a serious threat "as it was just pursuant to the scenario for a preemptive nuclear strike."
Assessments of North Korea's earlier launch revealed it included two short-range missiles that reached a max altitude of 30 miles and managed to go a distance of between 225 and 250 miles.