North Korea is estimated to be within a decade of having a weaponized nuclear device, says Rodger Baker, VP of strategic analysis at Stratfor.
Xinhua says the international community must remain calm to prevent chaos or war on the Korean peninsula.
The Democratic People's Republic of Korea says it tested a miniaturized nuclear warhead on Friday.
CNBC's Eamon Javers reports the U.S. government is reacting to North Korea's nuclear test, saying it is a "serious provocation."
North Korea claims to have successfully tested it most powerful nuclear detonation ever.
CNBC's Sri Jegarajah reports on market reaction to North Korea claims it successfully launched one of its most powerful nuclear weapon.
North Korea said it tested a miniaturized nuclear warhead on Friday as protection against "threats and sanctions" from hostile elements.
China's Xinhua news agency, the mouthpiece of Beijing, quickly urged restraint over the "unwise" nuclear test by North Korea.
North Korea has picked up the pace of its missile and nuclear tests, as it regularly threatens to turn South Korea into a "sea of fire."
North Korea said it tested a miniaturized nuclear warhead on Friday, in response to the "threats and sanctions from hostile elements." SBS CNBC’s June Yoon reports.
The latest test appears to be bigger than any of North Korea's previous experiments, says Bruce Bennett, senior defense analyst at RAND.
Ties between China and North Korea have cooled but whether the latter will stop its tests still depends on China, says Pusan National Uni's Robert Edwin Kelly.
President Obama talks about North Korea's nuclear build-up and China's relations with North Korea.
The missile launches were the latest in a series of launches by the isolated North this year in violation of U.N. Security Council resolutions.
North Korea’s latest missile test has security analysts admitting the country is closer than ever to possessing a nuclear weapon system.
What can be done to stop North Korea's hostile missile technology? The answer is, very little, unless the world's superpowers cooperate.
Kim Jong Un supervised a missile launch that he said put North Korea in the "front rank" of nuclear powers.
North Korea fired a submarine-launched ballistic missile off its east coast, the latest in a string of missile launches by the isolated country.
Tensions on the Korean Peninsula are ratcheting up, which is just what North Korea wants, as it pits China and the U.S. against one another.
The military drills signal U.S.' and South Korea's commitment to deter any provocations from North Korea, says The Korea Society's Thomas Byrne.