In early June, the group made a similar request to the government in a bid to check their facilities ahead of the summer rainy season. A total of 124 local firms ran factories at the industrial park, employing over 54,000 North Korean workers and producing labor-intensive goods such as clothes and utensils.

On Feb. 10, South Korea shut down the factory zone, some 50 kilometers northwest of Seoul, in response to the North's fourth nuclear test and long-range rocket launch early this year.

The companies have claimed that they have suffered more than 815 billion won ($696 million) in losses from the shutdown, adding that a set of government support measures are not enough to cover their damage.

The ministry said that 86 companies have received insurance claims worth of 254 billion won so far.

South Korean nationals need Seoul's approval as well as the North's consent for a trip to the communist nation. The two Koreas still remain technically at war since the 1950-53 Korean War ended in a truce, not a peace treaty.

The industrial complex, which opened in 2004, served as a major revenue source for the cash-strapped North, while South Korea has benefited from cheap but skilled North Korean labor. (Yonhap)