Belgian gold dealer Alain Goetz and a network of companies have been sanctioned by the US for allegedly smuggling hundreds of millions of dollars worth of gold from the Democratic Republic of Congo.
The US government says since 2016 Mr Goetz has been trading illegally in gold that has come from Congolese mines controlled by armed groups who often use forced labour or exploit miners.
US treasury official Brian Nelson says that conflict gold provided the largest source of revenue to armed groups in eastern DR Congo.
He says Alain Goetz and his network have contributed to armed conflict by receiving DRC gold without questioning its origin.