The US government has announced sanctions against three people and nine companies, including four based in Hong Kong and four in the United Arab Emirates, for aiding Iran’s shipment of oil to China, Reuters reports. The ninth company is based in Oman.

Treasury said the new designations by the Office of Foreign Assets Control (OFAC) were aimed at individuals and entities that helped Iran’s Islamic Revolutionary Guard Corps sell and ship its allotment of Iranian oil to China using a series of front companies.