North Korea nuclear test expected

North Korea could be almost ready to carry out its threat to conduct a nuclear test, a US research institute said, pointing to recent satellite photos.

The images of the Punggye-ri site where nuclear tests were conducted in 2006 and 2009 reveal that over the past month roads have been kept clear of snow and that North Koreans may have been sealing the tunnel into a mountainside where a nuclear device would be detonated.