The Top of Los Angeles police have refused to rule out put to death in the inquiry into the death of singer Michael Jackson, two weeks agoe
Police Chief William Bratton told US news journalist CNN that police were pending toxicology results.
"Are we dealing with a homicide or are we dealing with accidental overdose... I don't have that in sequence."
Meanwhile, Jackson's father, Joe, 79, talking about the death on ABC News, said: "I do think it was unclean play."
Jackson - who is due to attend a monument overhaul in the family's hometown of Gary, Indiana, later - has before said he had "a lot of concerns" over events surrounding his son's death, and that the family "suspected foul play somewhere".
The Los Angeles coroner has said that an autopsy the day after the singer's death revealed no evidence of foul play and that toxicology test results could take weeks to come back.
