NORTH KOREA, May 24: North Korea carried out what it said is the demolition of its nuclear test site Thursday, setting off a series of explosions over several hours in the presence of foreign journalists.

WONSAN, North Korea, May 22:  A small group of foreign journalists arrived in North Korea on Tuesday to cover the dismantling of the country’s nuclear test site later this week, but without South Korean media initially also scheduled to participate.

SEOUL/WASHINGTON, April 29: North Korea leader Kim Jong Un has promised to close his main nuclear weapons test site in May and said he will invite South Korean and American media to witness the shutdown.

TOKYO, Sept 3:  North Korea announced it detonated a thermonuclear device Sunday in its sixth and most powerful nuclear test to date, a big step toward its goal of developing nuclear weapons capable of striking anywhere in the U.S. The North called it a "perfect success" while its neighbors condemned the blast immediately.

WASHINGTON, August 13: U.S. intelligence officials are pretty sure North Korea can put a nuclear warhead on an intercontinental missile that could reach the United States. But experts aren’t convinced the bomb could make it all that way intact.

WASHINGTON, August 12:  No need to duck and cover just yet. While U.S. intelligence officials are pretty sure North Korea can put a nuclear warhead on an intercontinental missile that could reach the United States, experts aren't convinced the bomb could survive the flight to America.

SEOUL, May 15: North Korea on Monday boasted of a successful weekend launch of a new type of “medium long-range” ballistic rocket that can carry a heavy nuclear warhead.

SEOUL, Sept 9: North Korea on Friday conducted its fifth nuclear test, producing its biggest-ever explosive yield, South Korean officials said, with the South's president calling the atomic detonation an act of "fanatic recklessness."