The nuclear test conducted by North Korea was equivalent to 550 tons of TNT, a state-run South Korean geological institute said, which would be far smaller than the nuclear bombs dropped on Japan in World War II.
"It amounts to detonating 550 tons of trinitrotoluene, or TNT, at once," said Park Chang-soo, a spokesman of the Korea Institute of Geoscience and Mineral Resources.
North Korea claimed earlier Monday that it successfully conducted its first nuclear bomb test, the AP reports.
The atomic bomb that was dropped on Hiroshima of Japan on Aug. 6, 1945, had the destructive power of about 15,000 tons (33 million pounds) of TNT. Another bomb that was dropped in Nagasaki was equivalent to about 21,000 tons (46.2 million pounds) of TNT.
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