美国有线新闻 CNN 俄罗斯军事试验场发生爆炸 致5名核专家遇难（在线收听）

Day three of our Fall production season begins in Russia. Last Thursday there was an accident —an apparent explosion that killed at least five nuclear scientists at a military test site. But the nation's government didn't speak out about it until yesterday, when a Russian government spokesman said that accidents happen, and that Russia was still, quote, "far ahead in developing advanced weapons."

There's an international mystery surrounding this incident. For one thing, it happened in a city of northern Russia that's only accessible by permit and it's closed off to international visitors. For another, officials in the area said there was a temporary rise in radiation levels after the explosion took place, though the Russian government says radiation levels were normal. Overall, that government has been pretty secretive about this incident in general. It says a blast did take place last week but that it involved liquid fuel. And all this has analysts around the world speculating that they don't know for sure that the explosion involved a nuclear powered cruise missile. Here's why that's significant.

Last year Russian President Vladimir Putin said his country had developed new weapons, ones that would make U.S. missile defenses ineffective. He said a new Russian missile would have an unlimited range, and suggested it could avoid defense missiles for as long as needed. An accident at a secret military test range could come as an embarrassment to the Russian government, and it has a lot of control over the nation's media, so it's possible that information about this explosion is intentionally being kept quiet, which has some analysts suggesting this is a cover up. Back in 1986, what was then the government of the Soviet Union initially tried to cover up an explosion at the Chernobyl Nuclear Power Plant. To be clear, whatever happened last Thursday did not appear to have given off a large plume of nuclear radiation like the Chernobyl disaster did. But more than 30 years later, Chernobyl's effects are still rippling across Russia.