GANG members who blackmailed a shopowner and then warned witnesses against identifying them were yesterday given custodial sentences. Deputy Judge Davies said the four young men involved had been described as amateurs who did not intend to carry out their violent threats. However, the shopkeepers had been genuinely frightened. He jailed Li Kong, 23, whom he called the leader of the protection racket, for 21 months. Li admitted blackmailing Fong Chun-chun, who ran the Wui Chun Yuen Chinese medicine shop on Wah Fu Estate, in May 1992. But Li was acquitted of trying to extort $2,000 a month from the owner of the Wah Fu Dispensary, Wong Shing-kin. Wan Yee-tin, 17, also denied that charge but was found guilty and sent to a detention centre. Wan Pak-cheung, 18, and Cheung Chuk-cheung, 18, were both found guilty of criminal intimidation and attempting to pervert the course of justice. The teenagers had threatened to hurt the family of neighbour Ma Hung-piu if Mr Fong attended the identity parade. They also ordered Mr Ma to persuade Mr Fong not to attend the parade, but he refused. Wan was sent to a training centre and Cheung to a detention centre. Defence counsel for Li was Terence Wai and for the other defendants, Wong Man-kit.