Anchor: In an exclusive, the South Korean government has revealed to KBS that North Korea is building walls within the demilitarized zone, a strip of land some 250 kilometers long and some four kilometers wide between the two Koreas. The latest comes after North Korean leader Kim Jong-un said earlier this year that border installments connecting the two Koreas must be severed.   
Kim Bum-soo has more. 

Report: North Korea is building walls within the heavily-fortified demilitarized zone(DMZ) between the two Koreas. 

A South Korean government official on Friday revealed the latest findings to KBS, noting that the walls are being built simultaneously at eastern, central and western locations within the buffer zone.

The official said North Korean construction workers and their equipment were detected by surveillance assets in the South.

The workers were also said to be building tactical roads connecting the walls and the North.

Dozens of North Korean troops earlier this week briefly trespassed into the southern side of the DMZ and crossed back after the South Korean military fired warning shots. 

The South Korean government believes the incursion also had to do with the construction of the walls as many North Korean soldiers were then seen holding shovels and picks. 

Earlier this year, North Korea planted mines in the Gyeongui and Donghae land routes connecting the South to the now shut-down inter-Korean Gaesong industrial complex and the Mount Geumgang resort in the North. 

Then in March, North Korea removed street lamps along two inter-Korean roads, which were once seen as symbols of inter-Korean cooperation, and in the following month, the North planted landmines in the northern side of the DMZ. 

These actions were taken after North Korean leader Kim Jong-un said in his New Year speech that inter-Korean connections in the border areas must be completely severed. 
Kim Bum-soo, KBS World Radio News.