Updated April 17, 2022 at 9:23 AM ET

SEOUL, South Korea — North Korea has test-fired a new type of tactical guided weapon designed to boost its nuclear fighting capability, state media reported Sunday, days after it passed its biggest state anniversary without an expected military parade, which it typically uses to unveil provocative weapons systems.

The test, the 13th round of weapons launches by Pyongyang this year, came amid concerns that North Korea may soon conduct a larger provocation like a nuclear test in an effort to expand the country's weapons arsenal and increase pressure on its rivals amid stalled diplomacy.

The official Korean Central News Agency said leader Kim Jong Un and other top officials observed the launch. It said the weapon tested has "great significance in drastically improving the firepower of the frontline long-range artillery units, enhancing the efficiency in the operation of (North Korea's) tactical nukes of and diversification of their firepower missions."

KCNA didn't elaborate, but the mention of the word "tactical nukes" suggested the weapon is likely capable of carrying a battlefield nuclear warhead that could hit strategic targets in South Korea, including U.S. military installations. The KCNA dispatch didn't say when and where the launch occurred.

"North Korea is trying to deploy not only long-range nuclear missiles aimed at American cities but also tactical nuclear weapons to threaten Seoul and U.S. bases in Asia," said Leif-Eric Easley, a professor at Ewha University in Seoul. "Pyongyang's purposes likely exceed deterrence and regime survival. Like Russia employs the fear it could use tactical nukes, North Korea may want such weapons for political coercion, battlefield escalation and limiting the willingness of other countries to intervene in a conflict."

Some observers speculated the weapon tested Sunday might be a smaller, lighter version of North Korea's nuclear-capable KN-23 missile that has a highly maneuverable and lower-trajectory flight aimed at defeating missile defense systems. Others said it could be a new missile that combines the technical characteristics of the KN-23 and another short-range ballistic missile called the KN-24.

South Korea's Joint Chiefs of Staff said in a statement Sunday that it had detected two projectile launches from the North's eastern coastal town of Hamhung early Saturday evening.

It said the projectiles flew about 110 kilometers (68 miles) at an apogee of 25 kilometers (16 miles) and at a maximum speed of Mach 4. The statement said South Korean and U.S. intelligence authorities are analyzing additional details of the launches. South Korea's presidential office said officials have met twice this weekend to discuss the North Korean military activities.

North Korea has started this year with a slew of weapons tests, including its first flight test of an intercontinental ballistic missile since 2017. South Korean and U.S. officials said Pyongyang could soon launch additional provocations like another ICBM test, a rocket launch to put a spy satellite into orbit or even a nuclear test explosion that would be the seventh of its kind. South Korea's military said it has detected signs that North Korea is rebuilding tunnels at a nuclear testing ground it partially dismantled weeks before it entered now-dormant nuclear talks with the United States in 2018.

Sunday's KCNA dispatch quoted Kim as presenting unspecified tasks to build up North Korea's nuclear combat forces and its defense capability after praising what he called successive progress in its efforts to reinforce the country's war deterrence power.

The North's recent testing activity involved the sophisticated weapons systems Kim has vowed to introduce to cope with what he calls American hostility. Analysts say North Korea may perform more missile tests after the South Korean and U.S. militaries begin their annual drills this week because North Korea views them as an invasion rehearsal.

"North Korea has a domestic imperative to make and perfect weapons ordered by Kim Jong Un last year regardless of what the U.S. does or doesn't do. The test also tells his people that their country is strong despite their apparent economic difficulties," said Duyeon Kim, a senior analyst at Washington's Center for a New American Security. "One reason for the political timing could be to protest anticipated U.S.-South Korea military drills."

On Friday, Kim attended a massive civilian parade in Pyongyang that marked the milestone 110th birth anniversary of his state-founding grandfather, Kim Il Sung. It appeared the country passed its most important national holiday without a highly anticipated military parade to showcase its new weapons systems.

Kim may still hold a military parade on the April 25 founding anniversary of North Korea's army. But if that anniversary goes without a military parade again, some experts say that might mean Kim doesn't have new powerful missiles to display and that his next provocative step will likely be a nuclear test.

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