North Korea fired two ballistic missiles into the Sea of Japan on Monday, the Defense Ministry said, with Pyongyang warning of more launches over the Japanese archipelago as the United States and its East Asian allies held joint exercises.

The two missiles appear to have fallen outside Japan's exclusive economic zone, and there were no reports of damage to aircraft or ships, the Japanese ministry said. The launch followed the North's firing Saturday of an intercontinental ballistic missile.

Footage broadcast by Korean Central Television on Feb. 20, 2023, shows what appears to be a ballistic missile launched by North Korea on the same day. (Kyodo)

The first missile was launched around 6:59 a.m., reaching an altitude of about 100 kilometers and traveling about 400 km, while the second was fired around 7:10 a.m., reaching an altitude of about 50 km and traveling about 350 km, according to the ministry.

Kim Yo Jong, the younger sister and a close aide of North Korean leader Kim Jong Un, said in a statement carried by the country's official Korean Central News Agency on Monday, "The frequency of using the Pacific as our firing range depends upon the U.S. forces' action."

The United States held air drills separately with Japan and South Korea on Sunday. Washington and Seoul are also scheduled to conduct tabletop exercises on Wednesday against nuclear threats and the 11-day Freedom Shield field training exercises in mid-March.

North Korea "will take corresponding counteraction" if U.S. actions are "judged to be any direct or indirect threat," said the sister, vice department director of the Central Committee of the Workers' Party of Korea.

Prime Minister Fumio Kishida told reporters that Japan has requested an emergency U.N. Security Council meeting over the latest North Korean missile launches, emphasizing Tokyo will work closely with the United States and South Korea to tackle regional security threats.

The Security Council has decided to hold a meeting on Monday afternoon, according to Malta, which currently serves as its chair.

The Japanese government said it had lodged a protest with North Korea via the embassy in Beijing.

Chief Cabinet Secretary Hirokazu Matsuno, the top government spokesman, criticized Pyongyang's missile launches, telling a news conference, "The series of actions by North Korea are totally unacceptable as they threaten peace and safety in Japan, the region and international society."

Kim Yo Jong, North Korean leader Kim Jong Un's sister, pictured in Pyongyang in September 2018. (Kyodo)

Foreign Minister Yoshimasa Hayashi said at an event in Tokyo that North Korea's "repeated ballistic missile launches with unprecedented frequency" pose a "grave and imminent threat" to Japan's security.

The South Korean military said two short-range ballistic missiles were fired from the Sukchon area in South Pyongan Province in North Korea's west.

KCNA reported Monday that the Korean People's Army set virtual targets 395 km and 337 km away from launching points, respectively, and fired two shells from large-scale 600-millimeter multiple rocket launchers.

The shells were launched by sub-units of the North Korean military's long-range artillery unit on the western front, the news agency said, calling them "a tactical nuclear attack means."

On Saturday, North Korea also conducted a "surprise" drill of the Hwasong-15 ICBM on a lofted trajectory, according to KCNA, which said the missile flew 989 km for 66 minutes and 55 seconds, reaching a maximum altitude of 5,768.5 km.

The Japanese government said the missile appeared to have fallen into the nation's EEZ off its northern territory but added it could potentially travel over 14,000 km on a normal trajectory and strike anywhere on the U.S. mainland.

The South Korean Foreign Ministry said Monday that Seoul had decided to impose additional sanctions against four individuals and five institutions connected to North Korea in response to the launches earlier in the day and on Saturday.

A Hwasong-15 intercontinental ballistic missile is launched on Feb. 18, 2023, in Pyongyang. (KCNA/Kyodo)

"The military will trace and monitor movements under close cooperation between South Korea and the United States in preparation for additional provocations from North Korea and form a firm readiness posture based on South Korea-U.S.-Japan security cooperation," the South's Joint Chiefs of Staff said in a statement.

The U.S. Indo-Pacific Command said North Korea's launches highlighted the "destabilizing impact" of its "unlawful weapons" of mass destruction and ballistic missile programs.

"The U.S. commitments to the defense of the Republic of Korea and Japan remain ironclad," the command said in a statement, referring to South Korea by its official name.

Chinese Foreign Ministry spokesman Wang Wenbin expressed hope that all parties related to the situation on the Korean Peninsula will explore political settlement and resolve their respective concerns in a balanced manner through meaningful dialogue.

Beijing will "continue to play a constructive role in promoting the political settlement of the peninsula issue," he said at a press conference Monday. China is North Korea's closest and most influential ally in economic terms.

Immediately after North Korea's launches on Monday morning, the Japan Coast Guard said Pyongyang had fired three projectiles, citing data from the Defense Ministry. But the ministry corrected the report later in the day, saying the North had launched two missiles.

Matsuno said the Cabinet Secretariat, a governmental body that gathers data from the Defense Ministry and other administrative organizations, mistakenly sent a notification about the second missile launch by North Korea to the Japan Coast Guard twice.

The first ICBM test by North Korea this year came after 2022 saw the country launch various types of missiles on a record 37 occasions.

There are also mounting fears that Pyongyang may be preparing to conduct its seventh nuclear test.

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