Transcript for Russian nuclear monitoring stations go silent after explosion
We move overseas to the mystery surrounding that deadly nuclear blast in Russia. Reports that two radiation monitoring stations have gone silent are raising new concerns and James Longman is back with the latest. Good morning, James. Reporter: Yeah, good morning. That's right. When I was there people told me they were mostly concerned because they weren't getting enough information and now these radiation systems have gone offline. The picture isn't getting any this morning, Russia's radiation mystery deepens since that nuclear missile malfunction nearly two weeks ago radiation detection sites across the country are going silent. According to an international nuclear watch dog two bases went dark August 10th then three days later two further sites stopped transmitting. Why? Russia won't say. But it's possible authorities are trying to hide data that these sites could have detected following the nuclear blast. That killed five Russian scientists and two military personnel and prompted an evacuation later canceled. Speaking yesterday, Vladimir Putin said there was no contamination risk or danger of radiation. But given this concern is a top secret missile project much of what happens remains a mystery and Russia has sought to hide secrets before and this is on a totally different scale than chernobyl. The tragedy surged back into the global spotlight thanks to the popular HBO series. And all this comes as a u.s./russian nuclear treaty fell apart earlier this month. Though not nuclear the U.S. Is now testing missile systems not seen since the cold war. You have to ask are we on the brink of another arms race? Could be dangerous. Thanks very much.
This transcript has been automatically generated and may not be 100% accurate.