Police are investigating a murder case after a man was found unconscious at home and later declared dead at hospital. Officers said they received a report from the deceased's father at around 1am on Sunday that his son, 35, had fainted at their home in Yau Oi Estate in Tuen Mun. The victim was rushed to hospital where he was pronounced dead. Sources said the man had been beaten, and that police have made at least one arrest. An autopsy will be carried out to determine the cause of death.