"North Korea fires unidentified projectile southward" over the Yellow Sea, the South Korean Joint Chiefs of Staff (JCS) said, after Seoul, Beijing and Tokyo held their first trilateral summit since 2019.

Seoul said "multiple projectile fragments" were found in waters after the launch from Pyongyang.

The South's Joint Chiefs of Staff said in a statement that it first detected the projectile's trajectory at 10:44 p.m. (1444 GMT) from the Tongchang-ri area -- where the North's Sohae Satellite Launching Station is located -- towards the East Sea, the name the two Koreas use for the Yellow Sea.

"The projectile was detected as multiple fragments scattered on the surface of the North Korean territorial waters at around 10:46 p.m. (1446 GMT), and the South Korean and US authorities are closely analyzing whether the flight was normal," it added.

Given that the initial detection of the projectile's trajectory was just two minutes apart from the second detection of fragments, it is believed to have exploded shortly after liftoff, marking another apparent failed attempt by the North to advance its space program after two botched launches of its Chollima-1 rocket in the spring and summer of 2023.

In November, Pyongyang finally succeeded in launching the rocket and putting its first spy satellite, the Kwangmyongsong-1, into orbit.

Japanese government spokesman Yoshimasa Hayashi told a press conference that the projectile "disappeared (from radar) in mid-air over the Yellow Sea".

"We believe that it did not reach the level of an earth satellite," he added.

Japan's public warning system was initially activated in the southwestern prefecture of Okinawa after it detected and calculated the trajectory of the projectile, but it was lifted minutes later as it "did not pass over the designated area," a Japanese government source told Kyodo News.

Meanwhile, Japanese broadcaster NHK aired footage apparently taken from across the Chinese border with North Korea -- the Sohae base is located around 50 kilometers (30 miles) south of the Chinese city of Dandong -- showing an irregular-shaped combustion in the night sky, followed by what appeared to be an explosion.

Pyongyang earlier Monday notified Japan's coast guard of a launch window between Monday and June 3 to put another spy satellite into orbit.

North Korea said earlier this year that it would launch three more "Kwangmyongsong" spy satellites by 2024.

The success of the November launch is believed to have been in large part due to assistance from Russia, which has been ramping up since North Korean leader Kim Jong Un and Russian President Vladimir Putin held a summit in September 2023.

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