Hamhung, North Korea's largest industrial center, was opened to foreigners just two years ago. There's no hiding the poverty in the region.
The answer may be as simple as 'it was too risky.'
North Korean leader Kim Jong-un has recently been photographed with an unknown woman, causing international buzz.
Once completed, the North Korean reactor would be able to produce enough plutonium for a new bomb every year, according to the US-Korea Institute at Johns Hopkins University.
North Korea threat: Washington says it has traced the sale of truck parts North Korea used to transport missiles to a Chinese company. Is Beijing not fully enforcing sanctions on North Korea?