The railway explosion that killed more than 160 people, injured 1,300 and destroyed more than 8,000 homes in North Korea last week remains deeply shrouded in mystery, leading some observers to speculate that it was something other than a freak accident.
Pyongyang's totalitarian government has offered little explanation for last Thursday's disaster, except to say that a train carrying ammonium nitrate fertilizer had accidentally contacted an electrical line. Yesterday, North Korean officials issued a statement saying that the disaster's effects were similar to "100 bombs, each weighing one tonne" and that it resulted in "horrible human and material loss within the radius of four kilometres."
The blast occurred nine hours after North Korean dictator Kim Jong-il and his private train passed through the site, near the Chinese border. Mr. Kim has made no statements or public appearances since.
Rail-transport experts said yesterday that while ammonium nitrate is considered an explosive material and is a component in bomb construction, such rail-borne explosions are extremely rare and are considered highly unlikely when standard fertilizer is transported using conventional methods. To become highly explosive, it generally has to be mixed with other chemicals.
"It is inordinately rare -- I can't tell you about another case I've ever heard of," said Robert Halstead, president of IronWood Technologies, an engineering firm that has investigated hundreds of rail disasters on behalf of U.S. governments. "Certainly nothing we've ever done has involved ammonium nitrate, and nothing I've ever heard of -- most rail explosions involve [propane]or liquefied natural gas."
Yet transportation officials in Canada and the United States said in interviews yesterday that ammonium nitrate is classified as an explosive hazardous material in both countries and is frequently carried by rail.
Mr. Halstead and other experts acknowledged that North Korea's safety standards are likely far more lax than those in North America, and that it would not have been impossible for an explosion on this scale to be caused by accident.
Some North Korean defectors, however, insisted that the possibility of an assassination attempt, or an explosion staged to attract international attention, was highly likely given North Korea's past behaviour.
"There is a possibility that some terrorists or rebellious groups wanted to kill Kim Jong-il," Kim Yong Sung, a 71-year-old defector, said at a Washington press event yesterday, according to Agence France-Presse.
James Lilley, a former U.S. ambassador to South Korea and China, speculated this week that the disaster may have been an assassination attempt. He said groups opposed to Mr. Kim "realize the system depends so much on him and the system is so bad and punitive that some people could have just taken the situation into their own hands."
Mr. Kim travels almost exclusively by train and makes frequent visits to China. North Korean defectors say that these trips often invite disaster, since the Korean transportation system is expected to come to a halt.
"So, right after Kim Jong-il arrives at some destination, all the other trains start moving again," An Hyuk, another defector, said in Washington. "Because of these complications, whenever Kim goes somewhere, after that a lot of trains hit each other and [cause]a lot of train accidents."
Indeed, some experts on the Pyongyang regime said that disorganization and incompetence were the most likely causes of the blast.
"The circumstances which allowed an incident of this magnitude to come about, and the official response to it, may or may not reflect very well on the North Korean government, but it seems a bit far-fetched to suggest complicity," said Adam Ward, a North Korea specialist with the International Institute for Strategic Studies in London.