The Los Angeles chief medical examiner has found Michael Jackson's death was caused by lethal levels of propofol, a powerful anesthetic.
In court documents unsealed in Houston on Monday, the coroner says the singer suffered cardiac arrest and died due to lethal levels of the drug, also known as diprivan.
Jackson, 50, died on 25 June at his Los Angeles home.
A police investigation appears focused on the use of prescription drugs and doctors who treated him, including his personal physician, Conrad Murray.
The BBC reports Dr Murray, has been interviewed twice by police but has not been named as an official suspect.
On the morning of the singer's death, Dr Conrad is reported to have given Jackson a lower dosage of propofol after a number of other drugs had not worked.
Jackson is to buried on 3 September at the Forest Lawn cemetery in Los Angeles.