The Hong Kong government had not yet requested any assistance from its Thai counterparts over Derek Wong Chong-kwong's possible whereabouts, security officials said in Bangkok last night. Wong is related to the well-known Thai-Chinese Kanjanapas business family in Thailand. His cousin is Keeree Kanjanapas, founder and chief executive of the Bangkok Mass Transit skytrain railway. The debt-saddled railway is planning its initial public offering on the Thai bourse early next year. Mr Keeree, also known as Wong Chong-shan, controls Thai-listed Tanayong and Hong Kong's Hwa Kay Tai Holdings. Despite earlier talks between Thailand and Hong Kong, no extradition treaty yet exists between the two jurisdictions. But the two sides do have an arrangement to exchange prisoners after conviction.