North Korea says it may test hydrogen bomb over Pacific Ocean

Show Caption Hide Caption North Korea threatens to test hydrogen bomb on unprecedented scale In retaliation for President Trump’s threat to destroy North Korea, the country says it might test a hydrogen bomb over the Pacific Ocean.

North Korea threatened early Friday to detonate a hydrogen bomb over the Pacific Ocean in what the nation called the "highest level of hardline countermeasure in history." The threat followed news that President Trump's administration would impose further sanctions on Pyongyang for its missile and nuclear weapons program.

The warning was delivered by North Korean Foreign Minister Ri Yong Ho in New York, according to comments published by South Korea's Yonhap news agency. Ri did not elaborate on when the detonation might take place and added that any final decision on the matter would be taken by North Korean leader Kim Jong Un.

North Korea has never tested a nuclear device beyond its own borders. Were it to do so in the Pacific Ocean it would represent a dramatic and worrying new stage in its showdown with Washington over its attempts to become a nuclear-armed state.

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The escalation in warring rhetoric came after Kim responded to Trump's "rocket man" speech at the U.N. General Assembly this week by branding him a "mentally deranged dotard" — an insult that has left many people reaching for their dictionaries to determine which leaders' comments were more offensive or inflammatory. In his speech to the U.N., Trump vowed to "totally destroy" North Korea if provoked.

More: Hydrogen bomb vs. atomic bomb: What's the difference?

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Kim said that Trump's remarks "convinced me, rather than frightening or stopping me, that the path I chose is correct and that it is the one I have to follow to the last." He described the president as "a rogue and a gangster fond of playing with fire."

The comments were released on official state media. They mark a rare direct intervention by the North Korea leader, who usually lets his deputies issue statements.

Trump waded back into the lengthening tit-for-tat Friday, saying on Twitter that "Kim Jong Un of North Korea, who is obviously a madman who doesn't mind starving or killing his people, will be tested like never before!"

Trump said Thursday he will ramp up economic pressure on North Korea by signing an executive order that cracks down on anyone who does business with the hermit nation. Even amid such sanctions and threats, Trump and his aides say they hope to resolve the stand-off over nuclear weapons without resorting to military action.

More: At U.N., Trump says he will sign new executive order to pressure North Korea

In recent months, North Korea has launched a pair of intercontinental missiles believed capable of striking the continental U.S. and another pair that soared over Japanese territory. Earlier this month, the North conducted its most powerful nuclear test to date, drawing stiffer U.N. sanctions. The war of words between the adversaries comes as the North moves closer to perfecting a nuclear-tipped missile that could strike America.

North Korea has conducted six nuclear tests. All of them have been underground. William McKinney, a scholar at the U.S.-Korea Institute of the Johns Hopkins School of Advanced International Studies, told Bloomberg an above-ground test — a test in the Pacific would be above-ground — has not been held in decades.

North Korea compares Trump to 'dog barking' President Trump isn't the only one name-calling in the war of words between the U.S. and North Korea. North Korean Foreign Minister Ri Yong Ho had this to say about Trump.

"If (North Korea) did, it would be condemned by everyone — the Chinese and the Russians would be just as upset as the U.S.," he told the news organization.

North Korea previously claimed to have tested at least two hydrogen bombs, though experts remain skeptical over whether it has done so. Hydrogen bombs are far more powerful than regular atomic bombs. Atomic bombs use fission to split a large atom into two smaller ones. Hydrogen bombs fuse two or more atoms into a larger one.

The atomic bombs dropped by the U.S. on Hiroshima and Nagasaki during World War II released explosive power equivalent to about 15 and 20 kilotons (1,000 metric tons) of TNT, respectively. The first hydrogen bomb tested by the U.S. in November 1952 released the equivalent energy of 10,000 kilotons (or 10 megatons) of TNT.