"Another possibility--the most disturbing one, actually--is that the North Koreans had been telling the truth when on May 12, just two days before South Korea detected the high levels of xenon, they announced they had created a nuclear fusion reaction, a step necessary to the building of a thermonuclear device. Xenon is released whenever uranium is enriched, such as when it is enriched for the core of a nuclear weapon."
yitbos
I do not think that the North Koreans are technically able to create a hydrogen bomb.I do not think they have the scientists capable for a development of a hydrogen bomb. The leadership can barely feed their people and maintain a 1.2 million man army. Anyways, the South Korean military and the Science ministry would have alerted the public of a threat.
Nope. Xenon is released when uranium fuel from a fission reactor is processed to extract plutonium (it is a product of the fission process, and is trapped in the fuel rods until they are dissolved in acid). It's still a sign of bomb-making, but not uranium-based bombs.