The North has put posts on a six-mile stretch along a narrow tributary of the Yalu River, which marks the border between North Korea and China. It has also built a road to guard the area, Yonhap news agency reported. The North has yet to string barbed wire fencing between the posts, the report said.
Less than a year ago, China built a massive barbed wire and concrete fence along its side of the same river.China had left their border lightly guarded but it has became a security concern for Beijing in the past decade as tens of thousands of North Korean refugees began trickling across into northeast China.
Many of the refugees take a long and risky land journey through China to Thailand, Vietnam, Cambodia and other Southeast Asian countries on their way to eventual asylum in South Korea.