A Korea expert speaks about the consequences of a fourth North Korean nuclear test.
The shells land in southern waters and nearly hit the vessel.
Authorities prohibit travel and limit market hours during a mass mobilization for spring planting.
North Korean state media says construction was not done properly in rare admission of culpability.
They bribe their managers to allow them to pursue more lucrative options.
More than 20 workers have died at the Baekdusan Songun Youth Power Station since late March, sources say.