North Korea test-fired what appears to have been a short-range submarine-launched ballistic missile into the Sea of Japan on Tuesday, the South Korean military said, the latest in a series of military provocations amid stalled denuclearization talks with the United States.

The Japanese government said it detected two ballistic missiles, noting they may have been submarine-launched and flew in an irregular trajectory, indicating they are likely of a type never seen before. There were no reports of any harm to aircraft or ships.

Japanese Prime Minister Fumio Kishida condemned the launch as a violation of U.N. Security Council resolutions banning North Korea from using ballistic technology and called it "extremely regrettable."

Kishida, who was in northeastern Japan to kick off campaigning for the Oct. 31 general election, rushed back to Tokyo to hold a National Security Council meeting.

"We are analyzing the details of North Korea's launch, including the possibility that they were SLBMs," Kishida told reporters afterward, adding that Japan will continue considering ways to bolster its missile defenses with one option being the acquisition of the capability to strike enemy bases.

Japan, the United States and South Korea reaffirmed their commitment to work toward the goal of ridding North Korea of its nuclear weapons, while agreeing to strengthen regional deterrence during a meeting of their senior officials in Washington, according to the U.S. State Department and a Japanese government source.

South Korea's Joint Chiefs of Staff said it detected a short-range ballistic missile being fired from waters near Sinpo on North Korea's eastern coast at around 10:17 a.m.

South Korea's Yonhap News Agency reported the ballistic missile flew around 590 kilometers and reached an altitude of about 60 km.

Japanese Defense Minister Nobuo Kishi told reporters one of the two ballistic missiles flew around 600 km and reached a maximum altitude of about 50 km before splashing down outside of Japan's exclusive economic zone. Japan is continuing its analysis of the other projectile, he said.

North Korea last test-fired an SLBM in October 2019, from Wonsan, also in the country's east. North Korea has a submarine-building shipyard in Sinpo.

The country showed a new type of SLBM in military parades in 2020 and this year, as well as at a defense exhibition held earlier this month.

The U.S. Indo-Pacific Command said in a statement that the launch "does not pose an immediate threat to U.S. personnel, territory, or that of our allies," while calling on North Korea to "refrain from any further destabilizing acts."

North Korea has test-fired a series of missiles in recent weeks. On Sept. 15 it launched two short-range ballistic missiles, the first such tests in nearly six months, and on Sept. 28 it launched what state-run media said was a newly developed hypersonic missile.

Japan's Deputy Chief Cabinet Secretary Yoshihiko Isozaki strongly condemned North Korea's continued test-firing of ballistic missiles as "threatening the peace and safety of Japan and the region."

Takehiro Funakoshi, head of the Japanese Foreign Ministry's Asian and Oceanian Affairs Bureau, spoke by phone with Sung Kim, U.S. special representative for North Korea, and agreed to keep up trilateral cooperation.

North Korea's latest missile launch coincided with a trilateral meeting joined by Funakoshi, Kim and Noh Kyu Duk, South Korea's special representative for Korean Peninsula peace and security affairs, in the U.S. capital.

The Japanese government source who briefed reporters on the meeting said the U.S. and South Korean officials respectively expressed their concerns over North Korea's latest action.

The officials also agreed to continue "diplomatic efforts" in dealing with North Korea, as well as ensuring the complete implementation of U.N. Security Council resolutions targeting North Korea's missile and nuclear weapons and work toward beefing up regional deterrence, the source said.

The administration of U.S. President Joe Biden has been reiterating its willingness to engage with North Korea toward denuclearization of the Korean Peninsula, but no progress has been seen so far.

During the meeting, Kim emphasized U.S. condemnation of North Korea's latest missile launch, and called on Pyongyang to refrain from "further provocations and engage in sustained and substantive dialogue," the State Department said in a press release.

While reiterating Washington's "ironclad" commitment to its key Asian allies, Kim also expressed support for humanitarian aid for the "most vulnerable North Koreans" and affirmed U.S. commitment to the immediate resolution of North Korea's past abduction of Japanese nationals, it said.

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