The death of Michael Jackson is now being officially treated as homicide.The Los Angeles County Coroner made the ruling, adding the singer was killed by the powerful anaesthetic Propofol and a cocktail of other prescription drugs. In the United States, homicide includes the crimes of murder and manslaughter. Jackson’s personal physician, Dr. Conrad Murray, was the subject of a manslaughter investigation, according to warrants police used to search his office. Murray has publicly maintained his innocence throughout the investigation. The police probe has focused on several other doctors responsible for the singer. Separately, Los Angeles police have now referred their investigation to prosecutors, who will decide whether to file criminal charges.