Several dead and injured in a Russian missile test accident. There are reports of high radiation levels from local authorities, but there is also speculation that the radiation claim is a ploy to keep people from picking up debris from the accident.
This sounds a bit like the aftermath of the Chernolbyl explosion.
Here is a Russian report that appears to answer some questions:
The five who perished had been working on an “isotope power source” for a propulsion system. An increase in background radiation was registered on the test site, but the measurements are said to have soon returned to normal.
If the rocket is propelled with some sort of nuclear power, then a radiation leak makes more sense. It looks like they may have resurrected an idea that dates back to the 1960s: