Report: Defense Department official says North Korea could develop hydrogen bomb

North Korea could develop a bomb more powerful than the atomic bombs dropped on Japan in the 1950's.

The bomb in question is a hydrogen bomb, also known as the ultimate atomic weapon.

It has the potential to kill millions of people, and North Korea reportedly might be able to develop one as soon as six to 18 months.

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The director of defense studies at the Center for National Interest Harry Kazianis -- who is also a North Korea expert -- wrote an opinion piece for Fox News about a U.S. Defense Department official who told him that North Koreans appear to be working to finish the development of a Hydrogen bomb.

"A Defense Department official I spoke to recently on the condition of not revealing his name told me it now appears the North Koreans are working to finish development of an H-bomb, and that they could succeed in as soon as six to 18 months," Kazianis writes. "Such a bomb would be many times more powerful than the atomic bombs the United States dropped on Hiroshima and Nagasaki in Japan that led to the end of World War II."

Last year North Korean Dictator Kim Jong Un claimed to have tested an H-bomb. Most experts argued that they had developed a more powerful atomic bomb, but not a hydrogen bomb.

Even if North Korea develops an H-bomb, some experts argue there is no clear evidence they have developed any type of atomic bomb small enough to fit on an intercontinental ballistic missile, or ICBM -- let alone develop a miniature H-bomb that would fit on an ICBM.

If they were successful in completing such a feat, an H-bomb could cause a death toll of over 1.7 million if it hit New York City.

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