China’s imports of copper and iron ore may drop due to an alleged financing scandal, as banks withhold credit and customs officials tighten checks on incoming shipments, metals traders say.

Western banks are looking into allegations that a Chinese trading company illegally pledged metals as collateral to more than one lender. The operator of Qingdao Port, the eastern Chinese port where the metals are stored, has confirmed that Chinese authorities are investigating allegations of fraud relating to stockpiles of metals.