A GRIEVING son was driven by his dead mother's voice to burn his father alive in order to stop him marrying another woman, the High Court heard yesterday. Li Wai-yi, 30, inflicted an agonising death upon his father, a doctor, by drenching him in boiling oil. Mr Justice Chan remanded Li for psychiatric reports and a probation report. He committed the killing after claiming to have heard his mother's voice begging him to put a stop to his father's plans to remarry. Li said the voice told him: 'He must be stopped. Do not let a woman lie in my bed. I cannot die for a second time.' The son killed his father, Li Fui-chun, 65, on May 15 last year, the day before the doctor was due to leave for China to go through with the wedding. He snatched a pan of oil which had been used to fry spring rolls and poured it over him, the court heard. The doctor's screams were heard by neighbours who called the police. The first constable to arrive on the scene was confronted by a horrifying sight. 'He found the deceased was soaked with oil and there were blisters on his body. The floor of the flat was also covered in oil,' said prosecutor Kumar Ramanathan. The doctor suffered burns to 40 per cent of his body, including his face, neck, chest, arms, hands and upper back. He died in hospital two days later. His son, who ran his own import-export business, appeared in the dock wearing spectacles and a smart suit. He pleaded guilty to manslaughter. His not guilty to murder plea was accepted by the prosecution on the grounds of diminished responsibility. Mr Ramanathan said two psychiatrists who had examined Li reported that he was suffering from depression. The killing took place at the family home in Westlands Garden, King's Road, Quarry Bay. The court heard Li, a committed Christian and church voluntary worker, had been devoted to his mother, Ng Chin-kwan, who died of liver cancer on February 7, 1994. He sacrificed his career in order to nurse her until her death. But there had been tension in the marriage between Li's parents for many years. The doctor was said to have beaten his wife as well as his son and daughter Li Wai-tuen. The son snapped and committed the killing after his father told him his mother had 'deserved to die'. They argued over this and over the doctor's plans to remarry. 'The defendant then went into the kitchen and filled a saucepan with some of the hot oil from the frying pan. He returned to where his father was, threw the oil over him, and left the premises,' said Mr Ramanathan. Finny Chan Fei-nai, defending, urged Mr Justice Chan to release Li, who has been in custody for almost a year. 'I am sure that this very sad incident will live with him for the rest of his life. This will be a punishment which is inherent in itself,' he said. Mr Chan read three testimonials from friends of Li who described him as a kind and caring man who was 'eager to serve and help others' and had an 'extraordinary admiration and love for his mother'. The judge described the case as 'exceptional' and said he was in two minds as to which sentence to impose. On the one hand Li had to be punished for the killing. But at the same time, said the judge, he deserved to be given a chance. Mr Justice Chan said he did not want to have Li detained in a psychiatric centre unless it was necessary. 'He looks very decent. I don't want to lock him up in a centre,' he said. But the judge was anxious that Li received some psychiatric help to recover from the trauma of killing his father, and the death of his mother. He was remanded in custody until May 8.