North Korea launched its purported spy satellite Wednesday, the South's military said, prompting confusion in Seoul as the city briefly issued an evacuation warning in error.
South Korea's military detected the launch of what Pyongyang has described as a military reconnaissance satellite from south of the "Tongchang County area of North Pyongan Province in North Korea, at around 6:29 today," the Joint Chiefs of Staff said.
"Our military is checking whether it is flying normally," they added.
The military is analysing whether "what North Korea has claimed as a space launch vehicle" – ostensibly intended to carry a satellite into orbit – may have broken up in mid-air or crashed after vanishing from radar early, the Yonhap News Agency reported.
The "projectile disappeared from radar before reaching expected drop point," Yonhap said, citing the Joint Chiefs, adding that the military was looking at the possibility of it "exploding mid-air or crashing."
North Korea on Tuesday confirmed it planned to launch what it called "military reconnaissance satellite No. 1" before June 11, having told Japan of its plans a day earlier.
Tokyo and Seoul strongly criticised the proposed launch, which they said would violate UN sanctions barring Pyongyang from any tests using ballistic missile technology.
Because long-range rockets and space launchers share the same technology, analysts say developing the ability to put a satellite in orbit would provide Pyongyang with cover for testing banned intercontinental ballistic missiles (ICBMs).
Soon after the launch, Seoul city authorities sent an emergency text message alert to residents saying: "Citizens, please prepare to evacuate and allow children and the elderly to evacuate first" as an air raid siren sounded in central Seoul.
The alert prompted consternation and confusion on Twitter before Seoul's interior ministry minutes later said the alert had been "incorrectly issued."
North Korea does not have a functioning satellite in space, experts say.
Since 1998, Pyongyang has launched five satellites, three of which failed immediately and two of which appeared to have been put into orbit – but signals from them have never been independently detected, indicating they may have malfunctioned.
North Korea said Tuesday its new spy satellite would be "indispensable to tracking, monitoring... and coping with in advance in real time the dangerous military acts of the US and its vassal forces."
Criticising US-South Korea joint military exercises, including ongoing large-scale live-fire drills, a top North Korean military official said Pyongyang felt "the need to expand reconnaissance and information means and improve various defensive and offensive weapons", state media reported.
Pyongyang, which typically does not give advanced warning of missile launches, has been known to inform international bodies of purportedly peaceful satellite launch plans.
It told Japan on Monday it would launch a rocket between May 31 and June 11.
In 2012 and 2016, Pyongyang tested ballistic missiles that it called satellite launches. Both flew over Japan's southern Okinawa region.
Japan briefly activated its missile alert warning system for the Okinawa region early Wednesday, lifting it after about 30 minutes.
Since diplomatic efforts collapsed in 2019, North Korea has doubled down on military development, conducting a string of banned weapons tests, including test-firing multiple ICBMs.
North Korean leader Kim Jong Un last year declared his country as an "irreversible" nuclear power and called for an "exponential" increase in weapons production, including tactical nukes.
Kim this month inspected the country's first military spy satellite as it was prepared for launch, and gave the green light for its "future action plan."
In 2021, Kim identified the development of such satellites as a key defence project for the North Korean military.
"Whether or not North Korea's current satellite mission is a success, Pyongyang can be expected to issue political propaganda about its space capabilities as well as diplomatic rhetoric aimed at driving a wedge between Seoul and Tokyo," Leif-Eric Easley, a professor at Ewha University in Seoul.
South Korea's foreign ministry earlier this week condemned the launch plan, saying the "so-called 'satellite launch' is a serious violation of UN Security Council resolutions banning all launches using ballistic missile technology."
"If North Korea eventually goes ahead with the launch, it will have to bear the price and pain it deserves."