Prosecutors in South Korea have raided Foreign Ministry offices as part of an investigation into accusations that officials were involved in share-rigging.
The scandal relates to an African diamond mine owned by a Korean company.
The BBC reports ministry personnel are suspected of issuing a statement in December 2010 that exaggerated the value of a diamond mine in Cameroon.
Investigators say friends and family were tipped off and made huge profits when the mine's share value shot up.
The statement said the mine contained more than 400 million carats of diamonds - more than twice the world's total annual diamond production. The statement was false.
Prosecutors on Monday examined computers and documents belonging to several staff at the ministry.
A BBC correspondent says corruption scandals are a regular feature of South Korean politics and attract a lot of attention, especially in election years.