North Korea fired a projectile the country claims to be a space launch vehicle early Wednesday, just days after after leader Kim Jong Un said Pyongyang planned to put a reconnaissance satellite in orbit.

A rocket detected at around 6:29 a.m. local time was fired southward from the Tongchang-ri area, South Korea’s Joint Chiefs of Staff said in a text message. The rocket flew over seas far west of Baengnyeong Island, JCS said. Japan’s Coast Guard said the missile had likely already fallen.

Japan issued a missile alert for the southern prefecture of Okinawa, which it later lifted. South Korea warned residents of Seoul to take shelter, an alert it later said was sent in error.

South Korea was analyzing the possibility that the rocket had crashed, according to Yonhap. Kyodo News cited a Japanese official as saying the launch may have failed.

Japanese Prime Minister Fumio Kishida told reporters he had been informed that North Korea had launched what was thought to have been a ballistic missile, and that there were no reports of damage so far.

Pyongyang’s plans to launch a rocket had drawn sharp criticism earlier in the week, prompting rebukes from both Seoul and Tokyo and prompting a three-way call between Japan, South Korea and the US.

Both Japan and South Korea said that any launch using ballistic missile technology would be a breach of United Nations Security Council resolutions. Both countries had urged North Korea to abandon the launch.

Japan’s Coast Guard had warned on Monday that a satellite rocket could be launched between May 31 and June 11.

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Broadcaster NHK earlier warned residents of Okinawa to stay inside sturdy buildings and keep away from windows.

A siren sounded early morning in Seoul for about 3 minutes. After the mobile alert was issued to seek shelter, pedestrians were seen rushing toward subway stops. Some people stopped walking on the streets to check their phones but they soon resumed their movements.

While North Korea has launched a barrage of missiles this year, it last launched a space rocket in February 2016, when the country claimed to have put an observation satellite into orbit as part of what it said was a lawful space program. The satellite is thought to have never reached orbit.

--With assistance from Youkyung Lee and Isabel Reynolds.

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