This is CBS. I am the world. I'm John Vacher with Gordon Chang at Gordon G. Chang, my colleague

and co-host. The headline, North Korea, security of Kim Jong Un, tightened, that's the quote,

as explosion rocks Pyongyang. Kim has included briefcase wielding security men in his protection

team rights reads the subhead. We welcome our colleague Greg Scarlato, director of the committee

for human rights in North Korea. Greg, a very good evening to you. Kim Jong Un, an increased

security ring around him. However, the explosion has it been confirmed and what could explain

an explosion in a large city. Good evening to you. Very good evening to you, John and Gordon.

North Korea doesn't have a still our safety record, whether it's about handling explosives

or handling construction work. We've seen pictures of North Korean construction workers

on scaffolding with no safety builds or no safety devices. That said, not every explosion

that happens in North Korea is an attempt on the leader's life. Of course, we do have

a precedent. On April the 22nd, 2014, a train exploded at Pyongyang train station close

to the border with China. There was a range of explanations ranging from the official explanation

by the DPRK, the North Korean government. It was an ammonium nitrate explosion. Syrian

scientists were killed in that explosion. So at the other end of the range was the explanation

that the train was actually transporting a Syrian, a liquid fuel missile. Anyway, Kim Jong

Il's train, this is the father of the current leader, Kim Jong Un. Kim Jong Il's train had

passed through Ryong-Ton station just a few hours before that. So there was speculation

that this might have been an attempt on Kim Jong Il's life. Now, any dictator will be paranoid.

Kim Jong Un is paranoid. The question is, does the scent exist in North Korea? Well, it

has existed over the years. In 1981, there are armed clashes between soldiers and workers

in Tungjin, in North Hong Kong province. There are massacres of hundreds of civilians

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