President Donald Trump says that North Korea "had best not make any more threats to the United States" or "they will be met with fire and fury like the world has never seen."
Trump issued the warning during a briefing on opioid addiction at his golf course in Bedminster, New Jersey.
A Japanese defense paper and a U.S. media report said Tuesday that North Korea may have successfully produced a miniaturized nuclear warhead that can fit inside its missiles.
That's a key benchmark in the country's attempt to become a full-fledged nuclear power.
Washington's alarm over North Korean leader Kim Jong Un's pursuit of a nuclear capability has intensified in the past month after the North conducted two tests of intercontinental ballistic missiles last month.
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Pres Trump: North Korea will be met with 'fire and fury'