SEOUL, South Korea (AP) — South Korea says that North Korea has fired a ballistic missile toward the sea but that the launch likely failed.

South Korea’s Joint Chiefs of Staff said Thursday the North Korean launch was made from the North’s capital region on Wednesday night.

It says the North Korean missile was believed to have failed but didn’t elaborate.

The North Korean missile launch came a day after it launched a spy satellite. North Korea has claimed to have put the satellite into orbit

South Korea decided to partially suspend an inter-Korean agreement and restart front-line aerial surveillance of North Korea, hours after the North claimed to have put its first military spy satellite into orbit in violation of United Nations (UN) resolutions, officials in Seoul said.

The South Korean announcement — which will likely infuriate North Korea — came as the North’s neighbours are trying to confirm whether the launch on Tuesday evening was successful and the satellite can perform reconnaissance functions.

South Korea’s military said it assessed that the North Korean spy satellite had entered orbit as the North claimed. But it said it needs more time to verify whether it works. Earlier, the Pentagon said it was assessing the success of the launch, while Japan stated there had been no confirmation of the North’s report on the satellite entering orbit.

North Korea’s state media claimed the spy satellite transmitted imagery showing space views of key military sites in the US Pacific territory of Guam. It didn’t publicise the photos, and many experts remain sceptical about whether the North Korean satellite is advanced enough to conduct meaningful military reconnaissance.

Despite questions about the launch, the United States and its allies strongly condemned it. They believe it was meant to improve the country’s missile technology as well as establish a space-based surveillance system.

North Korea says it has sovereign, legitimate rights to launch spy satellites to cope with what it calls intensifying US-led threats. But UN Security Council resolutions prohibit any satellite liftoffs by North Korea, viewing them as covers for testing its long-range missile technology.

Heo Tae-keun, South Korea’s deputy minister of national defence policy, told a televised briefing that the North’s latest satellite launch was not only a clear violation of the UN resolutions but also “a grave provocation that threatens our national security.”

Heo said South Korea decided to respond by partially suspending the 2018 inter-Korean agreement Wednesday and resuming aerial surveillance activities at the border. He added that South Korea will “promptly and strongly punish” North Korea if it uses the South Korean step as a pretext to launch another provocation.

The 2018 agreement, struck during a short-lived era of reconciliation between the rival Koreas, created buffer and no-fly zones along the countries’ heavily fortified border. Under the deal, the Koreas were required to halt front-line aerial reconnaissance and live-fire exercises. They also removed some of their guard posts and land mines at border areas.

The deal invited withering conservative criticism in South Korea with critics saying it significantly restricted the operation of the country’s aerial surveillance assets, which are much more superior to North Korea’s. They also accused the deal of heavily benefiting North Korea, because it only called for mutual reductions of conventional military strength while leaving the North’s growing nuclear arsenal intact. South Korea has no nuclear weapons.

The brief Korean rapprochement period evaporated soon after the collapse of broader nuclear diplomacy between North Korea and the US in 2019. North Korea has since ramped up missile tests to modernise its weapons arsenal, prompting the US and South Korea to expand their defence exercises in response.

When the North’s National Aerospace Technology Administration announced what it called a successful launch of its “Malligyong-1” spy satellite, it said the satellite would help improve the North’s war readiness in the face of “the enemies’ dangerous military moves.” The agency said North Korea will soon launch several more spy satellites to better monitor South Korea and other areas.

Leader Kim Jong Un watched the satellite launch on site. According to state media, Kim later visited the Pyongyang control centre of the North’s space agency, where he was briefed that the Malligyong-1 satellite would officially begin its reconnaissance mission from December 1, following a period of fine-tuning.

At the centre, Kim was also presented with the aerospace photos of Anderson Air Force Base, Apra Harbor and other U.S. military facilities in Guam, which were taken Wednesday morning, according to the North’s official Korean Central News Agency.

It was not possible to independently confirm those images. Last December, when North Korea released black-and-white satellite photos of South Korean cities following a test launch, many experts said the imagery was too crude for a surveillance purpose.

North Korea used the same satellite in its two failed launches in May and August. South Korea’s military retrieved debris from the first launch and assessed at the time the satellite wasn’t sophisticated enough to perform military reconnaissance.

In 2012 and 2016, North Korea placed Earth observation satellites into orbit, but experts say neither has ever transmitted imagery back to North Korea.

Before Tuesday’s launch, South Korean officials said North Korea was likely receiving Russian technological support for its spy satellite launch program as part of the two countries’ pushes to boost their partnerships.

The US, South Korea and others accuse North Korea of shipping conventional arms to support Russia’s war in Ukraine in exchange for receiving high-tech Russian technologies to enhance its own military programs. Both North Korea and Russia have denied the accusations.

A spy satellite is among an array of sophisticated weapons systems that Kim wants to introduce. Experts say he would eventually aim to use his enlarged arsenal to win sanctions relief and other concessions from the US when diplomacy resumes.

Some civilian experts said North Korea’s Malligyong-1 satellite is likely capable of only detecting big targets like warships or planes. But by operating several such satellites, North Korea could still observe South Korea at all times, they said.