Ryanggang explosion

The Ryanggang explosion was a large explosion that took place in North Korea on 9 September 2004 in the northern province of Ryanggang. The nature and cause of the suspected explosion is the subject of speculation. No neighboring nations have claimed any detection of radioactive isotopes characteristic of a nuclear explosion.

The suspected explosion was located near Wŏltan Workers' District (Wŏltal-lodongjagu) (41°19'47"N 127°05'02"E) in the county of Kimhyŏngjik in Ryanggang Province. This is in a mountainous region, about 1.5 km above sea level. The explosion was about 30 km from the border with China. The area contains several military installations, including munitions factories and a secret underground military base suspected to contain a uranium enrichment plant.

Early reports said that seismic activity had been detected early on 9 September 2004, and this was correlated with a "strangely shaped cloud", suspected to be a mushroom cloud. Together these would indicate a large explosion. The date, 9 September 2004, the 56th anniversary of the formation of North Korea, was taken as significant; North Korea has a history of making grand military gestures on significant dates. However, the original reports have been contradicted by later reports denying that there was any explosion.

The incident was not reported internationally until 12 September 2004, when the South Korean news agency Yonhap cited a source in Beijing, China, which said a mushroom cloud had been seen. Suspicion was raised by the fact that there was no mention of the explosion on internal North Korean media. However, North Korean news is usually a method employed by governing figures to make the ruling party's decisions more favourable to the people (national and internationally), therefore unfavourable stories are commonly not broadcast. The Ryongchon disaster earlier in 2004 was reported only several days after the event.

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