Michael Jackson took more than 10 Xanax pills a night, "asking his employees to get the prescription sleep medicine under their names and also personally traveling to doctor's offices in other states to obtain them," according to CNN.
The bombshell reports comes from a 2004 Santa Barbara County Sheriff's Department document that contains confidential interviews with two of Jackson's former security guards. The interviews were conducted as officials prepared for the singer's 2005 child molestation trial.
One security guard told sheriff's deputies that he expressed his concern to another staffer about Jackson's use of 10-plus pills a night.
According to CNN, the second staffer replied: "Jackson was doing better because he was down from 30 to 40 Xanax pills a night."
One of the guards said he and three other employees would get prescriptions for Jackson under their names.
The second guard supported the claim, adding that he had picked up medicine for the singer that were in other people's names.
Jackson would often appear "out of it and sedated," one guard said.
According to document, the guard who provided the bulk of the information told investigators he was not comfortable getting prescriptions for Jackson and eventually quit after Jackson "fell on his face" in a hotel room and hurt himself.
Detectives are investigating the singer's history of using prescription drugs and have spoken to a number of doctors who had treated Jackson over the years.
Police aren't ruling out homicide, but said they are "going to be very dependent on the toxicology reports."
Jackson died at the age of 50 after suffering cardiac arrest June 25.