SEOUL >> North Korea launched a ​barrage of ​short-range ballistic missile​s toward the waters off its east coast today, a day after the United States and South Korea completed a joint naval exercise involving an American aircraft carrier group, according to South Korean defense officials.

So far this year, North Korea has conducted 18 ​weapons ​tests ​involving dozens of missiles, more ​tests than in 2020 and 2021 combined. Today, it fired eight short-range ballistic missiles from the Sunan area of Pyongyang, the capital, and three other locations, the South Korean military said. Pyongyang’s international airport is in Sunan, and the North has fired missiles from there in the past.

The missiles, all launched within a 37-minute period, flew from 68 to 416 miles, the South Korean military said in a statement. It said it “sternly urged North Korea to stop serious provocations that harm peace and stability” on the Korean Peninsula.

In response, the South Korean and U.S. militaries fired eight surface-to-surface missiles off the east coast of South Korea early Monday to demonstrate their ability to target North Korean missile forces, South Korean defense officials said. Separately, Japan and the United States also conducted a joint ballistic missile exercise aimed at showing their “rapid response capability,” Japan’s Defense Ministry said.

The missile test by North Korea was its third since South Korea’s new president, Yoon Suk-yeol, was inaugurated May 10. He has promised to strengthen military cooperation with the United States, citing the threat of the North’s expanding weapons program.

On Saturday, the South Korean and U.S. navies completed a three-day joint exercise in international waters off the Japanese island of Okinawa, in the East China Sea, South Korean officials said​. The aircraft carrier USS Ronald Reagan ​participated in the drill, making it the first U.S.-South Korean drill since 2017 that involved a carrier. ​

Officials in Seoul and Washington expect North Korea’s flurry of weapons tests to continue. They say the North has prepared an underground testing site in Punggye-ri, in the country’s northeast, for a potential detonation of a nuclear weapon, which would be its first since 2017.

President Joe Biden met with Yoon in Seoul last month, and they agreed to discuss ​​expanding ​joint military exercises. The naval drill near Okinawa last week was held to follow up on that commitment, officials said, though the vessels involved were on their way to a previously scheduled multinational exercise near Hawaii.

Biden’s predecessor, Donald Trump, and Yoon’s, Moon Jae-in, had canceled or scaled down the two allies’ military drills, to which the North fiercely objects, as part of their diplomatic outreach to its leader, Kim Jong Un. Trump and Moon each met three times with Kim, but both left office with the North’s nuclear arsenal undiminished, and the North has doubled down on its weapons development.

Its previous test, on May 25, involved three ballistic missiles, including what South Korean officials said was a Hwasong-17, its largest known intercontinental ballistic missile. North Korea has tested ICBMs or their components six times since February​, despite a 2018 promise from Kim not to carry out such tests, according to South Korean defense officials.

The North appears to be trying to develop a variety of nuclear-capable missiles, a goal announced by Kim in January 2021. South Korean intelligence officials say the North’s most recent tests are also meant to show confidence that it can overcome ​its current wave of COVID-19 cases without internal instability or accepting outside aid​.

North Korea reported what it said was its first COVID-19 outbreak last month, declaring a “maximum emergency” and imposing a nationwide lockdown. ​It has refused offers from South Korea, the United States and international health organizations to provide vaccines​, saying that the situation was being “controlled and improved​.”

North Korea today reported 73,780 new suspected COVID patients, bringing its total to more than 4 million since late April. It has reported only 71 deaths.

Experts have cast considerable doubt on those figures​. Because the North has a shortage of testing kits and labs, it measures its outbreak by the number of people with fever symptoms, not actual positive tests. Even with that uncertainty factored in, the North’s reported death toll would amount to one of the world’s lowest COVID fatality rates, despite a threadbare public health system.

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This article originally appeared in The New York Times.

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