The Busan branch of the Korea Customs Service has arrested the head of a South Korean firm suspected of importing North Korean coal disguised as coal from China and Vietnam in 2017 and last year. Two other employees were booked without physical detention on Thursday. 

They are charged with importing five-thousand tons of North Korean anthracite worth around 700 million won from China in May of 2017 and reporting it as Chinese coal to customs authorities in Pohang. 

They made similar lies to import eight-thousand-200 tons of North Korean anthracite from Vietnam last June through the Pohang port.

Customs authorities said the suspects aimed to reap huge profit margins after the price of North Korean coal dropped sharply due to UN sanctions. UN Security Council Resolution 2371 adopted in August 2017 bans the North from exporting coal and other minerals.