Prince died of an opioid overdose, according to tests results obtained by law enforcement, the Associated Press reports.
A spokesperson for the Midwest Medical Examiners Office told Variety autopsy results are still unavailable.
The legendary singer was found dead at his Minneapolis estate on April 21.
The official, who was not authorized to speak to the media, spoke to the AP on condition of anonymity.
Prince was reportedly treated for a drug overdose six days before his death, TMZ reported.
More to come.
Maane Khatchatourian © 2016 Variety Media, LLC, a subsidiary of Penske Business Media; Distributed by Tribune Content Agency, LLC