A defector from North Korea is cautioning against underestimating Kim Jong Un when it comes to nuclear weapons   and he says President Donald Trump may be key to stopping him.Song Byeok escaped from the North in 2002 and currently resides in South Korea. In a new interview, he told The Independent the threat of nuclear war is real as long as Kim Jong-un is in power. I think Kim Jong Un could wage nuclear war if his power is threatened and that is why he needs to be removed as soon as possible,  he said.The 48-year-old defector used to create propaganda art for the regime, now he creates protest work.  AoLThese pictures show the inside of Pyongyang s 360ft deep metro system   that will double up as a nuclear bunker if war breaks out between North Korea and the US.Images show commuters using the world s deepest underground train system which includes two lines with a combined length of 18 miles beneath North Korea s capital.Construction work on the Pyongyang Metro started in 1968 and was inaugurated in 1973 by Kim Il Sung, the grandfather of current dictator Kim Jong-un.Watch this fascinating look into North Korea by photographer Andrew McLeod: And while it is usually busy with commuters, the depth of the subway system means citizens could also use it as a shelter should tensions between North Korea and America boil over into full-scale war.The trains are old carriages from Germany which were bought up by North Korea in 1999 as they were heading for the scrap heap. Pyongyang now claims the trains were built in North Korea, but despite attempts to conceal their origin, some old graffiti tags can be seen on the carriages.French photographer Eric Lafforgue captured these images during a trip to the hermit state and said there were only 17 stations on two lines.He said the fare was the equivalent of half a US cent  You have to validate your ticket at one of these automatic machines. But they did not work the day I visited. Instead, a train attendant checked was checking the tickets by hand.For entire story: Daily Mail 