The South Korean government says it is investigating eight ships over alleged illegal North Korean coal shipments. 

A Seoul official said the Korea Customs Service(KCS) has detected a total of nine cases involving illegal imports of North Korean coal, and been investigating eight ships and an undisclosed number of importers who brought in the coal using the vessels. 

The official said those subject to the investigation are suspected of being involved in illegal imports, fabrication of documents and violation of inter-Korean exchange cooperation laws, adding the government has already imposed a travel ban on some of them. 

An unnamed local bank was initially suspected among the suspects, but the official said no bank is currently being investigated.

The official dismissed potential negative ramification in case South Korea is turned out to have violated international sanctions on the North, saying that Seoul has closely cooperated with Washington on the issue.  

The official added the U.S. highly assesses Seoul’s faithful implementation of North Korea sanctions, so there will be no “disadvantages.” 

The KCS launched an investigation following media reports of recently revealed UNSC documents that indicated North Korea shipped its coal from Russia to a third country via South Korean ports twice, late last year.