North Korea attempted to fire a missile from its east coast early on Tuesday but the launch appears to have failed, South Korean officials said, in what would be the latest in a string of unsuccessful ballistic missile tests by the isolated country.
The launch attempt took place at around 5:20 a.m. Seoul time (04:20 p.m. EDT), said the officials, who asked not to be identified, without elaborating.
Tension in Northeast Asia has been high since North Korea conducted its fourth nuclear test in January and followed that with a satellite launch and test launches of various missiles.
Japan put its military alert on Monday for a possible North Korean ballistic missile launch.
"We have no reports of any damage in Japan. We are gathering and analyzing data. The defense ministry is prepared to respond to any situation," Japanese Minister of Defence Gen Nakatani told a media briefing.
"North Korea shows no sign of abandoning the development of nuclear missiles and so we will continue to work closely with the U.S. and South Korea in response and maintain a close watch on North Korea," Nakatani said.
South Korea's Yonhap News Agency said it appeared North Korea had attempted to launch an intermediate-range Musudan missile. North Korea attempted three test launches of the Musudan in April, all of which failed, U.S. and South Korean officials have said.
Yonhap quoted a South Korean government source as saying the missile was likely to have exploded at about the time it lifted off from a mobile launcher.
The flurry of weapons technology tests this year came in the run-up to the first congress in 36 years of North Korea's ruling Workers' Party early this month, where young leader Kim Jong Un further consolidated his control.
Tuesday's attempted launch appears to have been its first missile test since then, and experts have said it was unusual to test-fire a missile so soon after a previous failure.
The South Korean military said Pyongyang's continuous missile launches could stem from Kim's order in March for further tests of nuclear warheads and ballistic missiles.
"They must've been in a rush. Maybe Kim Jong Un was very upset about the failures," said Lee Choon-geun, senior research fellow at South Korea's state-run Science and Technology Policy Institute.