North Korea is blocking South Korean workers from passing through the joint industrial zone, Kaesong. This is a move by the North to further distance itself from the South ahead of possible war between the two states. Over 800 South Koreans were in the complex when the ban was announced. South Korean workers are being allowed into the industrial complex, but are not allowed to pass through into North Korea.

Kaesong is an important money-maker for the North, and is home to more than 100 factories. Over 50,000 North Koreans work there, and a few hundred South Korean managers. Every day, workers are granted permission to cross into Kaesong where they are also allowed to stay overnight..

Unification Ministry spokesman Kim Hyung-seok said:

South Korea’s government deeply regrets the entry ban and urges it be lifted immediately. Ensuring the safety of our citizens is our top priority and the South Korean government will take necessary measures based on this principle.

This is however not the first time that the North has placed a ban on movement into the zone. South Koreans were denied access to Kaesong in March 2009 due to a US-South Korea military exercise.

A steady stream of cars are moving back towards South Korea, but some South Koreans fear that if they leave they will not be allowed back in again, and have decided to stay. BBC correspondent, Lucy Williamson said any disruptions that affect Kaesong will have a negative economic effect of North Korea.

On Tuesday, the North threatened to restart its mothballed reactor at Yongbyon, which generates plutonium for its nuclear weapons programme. US Secretary of State, John Kerry said:

Let me be perfectly clear here today. The United States will defend and protect ourselves and our treaty ally, the Republic of Korea (South Korea).

Officials have confirmed that the USS John McCain destroyer capable of intercepting missiles, has been sent to the region and is positioned off the Korean peninsula. And a second destroyer, USS Decatur has also been sent to the region.

United Nations Secretary General Ban Ki-moon said:

Things must begin to calm down, there is no need for the DPRK [North Korea] to be on a collision course with the international community. Nuclear threats are not a game.

[Source: YouTube, BBC News]