Two potential reasons were given for the reported execution.
Mr Park could have been blamed for North Korea’s sixth and most powerful nuclear test being delayed, the defector said. The test was originally planned to take place in Spring, but was pushed back to 3 September due to delays in tunnel construction.
Experts have warned a series of tremors and landslides near the nuclear test facility probably mean the country’s latest nuclear blast has destabilised the region, and the Punggye-ri nuclear site may not be in use much longer.
Chinese scientists have warned that if the whole mountain collapsed, radiation could escape and drift across the region.
It is also possible Mr Park was held responsible for the reported collapse of a tunnel in October, which killed around 200 people, though North Korea has denied the reports. (The Independent)