Censor.NET reports citing CNN.
The missile flew east about 500 km (over 300 miles), South Korean officials said.
The missile was launched Sunday at about 4:59 p.m. Seoul time from a site in the vicinity of Puckchang county, which is home to North Korea's largest power plant.
It seems to have fallen into the Sea of Japan, also known as the East Sea, but not within Japan's exclusive economic zone, Japanese Chief Cabinet Secretary Yoshihide Suga said in a press briefing. Authorities have not received any reports of damage on ships or planes, Suga said.
A White House official said the projectile was a medium-range ballistic missile, a system that North Korea tested in February. The missile tested in February was a Pukguksong-2, a medium long-range ballistic missile, officials said. It was the first test by Pyongyang since President Donald Trump was inaugurated.