The Los Angeles County coroner's office announced Friday that Michael Jackson's death on June 25 was a homicide caused primarily by propofol and another sedative, and ruled propofol with other anti-anxiety drugs was a contributing factor in his death.
Jackson was using propofol to help him sleep, a practice medical experts consider extremely dangerous.
Joe Jackson said the coroner's announcement "tells me there was foul play done. That's what it tells me. And more to be investigated to see what is behind all of this stuff, not just Dr. Conrad Murray."
Murray, a Las Vegas cardiologist who was Michael Jackson's personal physician, hasn't been charged with any crime but he is the target of what police term a manslaughter investigation.
"Someone should pay. Not just someone but all of them should pay that's involved," Jackson said.