Why it's getting harder to escape from North Korea

Every year, hundreds of people make the perilous journey out of North Korea as they escape from the "hermit kingdom".

But the number of defectors has been steadily dropping in recent years, as North Korean authorities have clamped down.

Ha Jin-woo, a defector who left in 2014, used to help other North Koreans escape. He explains how the route to freedom has become even more arduous.