Scott Weiland, former lead singer for the Stone Temple Pilots and Velvet Revolver, died of an accidental overdose involving a combination of drugs, Rolling Stone reports, citing the Hennepin County Medical Examiner in Minneapolis.

Weiland, who was found dead Dec. 3 while on a tour stop in Bloomington, Minn., reportedly mixed cocaine, ethanol and MDA. The medical examiner also noted the rock singer’s history of asthma and atherosclerotic cardiovascular disease, along with his multi-substance dependence.

Weiland had a long, highly public battle with addiction.