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rt.com
The Russian army has joined the rescue operation. Radiation, chemical and biological protection units have been put on high alert. Since the explosion occurred several kilometers above the Earth, a large ground area must be thoroughly checked for radiation and other threats.
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Police in the Chelyabinsk region are reportedly on high alert, and have begun ‘Operation Fortress’ in order to protect vital infrastructure.
Last night on Coast to Coast they were reporting that it knocked out cell towers etc. in the region.
This thing was traveling so fast it was breaking the sound barrier. As I understand it that is some of the explosion sound you hear in the videos.
PS...
All space debris is potentially radioactive. Science knows that much from their travels and testing.
So yes, an explosion like this and the dust/debris may be highly contaminated.
The same was true when the space shuttle blew up over Texas. It is why they told people to stay away from the debris.