A factory worker was last night convicted of bludgeoning his boss to death with a sledgehammer. So Woon-kau, 37, showed no emotion as the High Court jury found him guilty of murdering Chan Ho-wai, 52, in April last year. Outside court, Chan's 46-year-old wife, Man Lai-chun, wept in the arms of her daughter, Chan Mei-lin, who said: 'This proves he really killed my father. He deserves this verdict. He did it because of gambling and now his whole life has been ruined,' said the 26-year-old. So and brother-in-law Pak Kam-shing cemented Chan's body in a 165-centimetre trough behind a toilet in Chan's Kwun Tong weaving factory. A pathologist's report said the victim may have been buried alive. The next day, the family received a blackmail demand for $6 million. So denied he murdered Chan and stole $5,000. He also denied blackmail but admitted unlawful burial of a body. The court heard he told police that he hit Chan. He added: 'I saw the boss was still alive and I hit him with the hammer once more. I hit him again and he did not move.' The jury found So guilty on each count he had denied. The maintenance worker will be sentenced by Mrs Justice Verina Bokhary today along with Pak, 38, who admits helping bury the body.