Tom Petty Death Certificate Cause Of Death Still a Mystery

10/10/2017 8:38 AM PDT

Tom Petty Death Certificate: Cause Of Death Still a Mystery

EXCLUSIVE

TMZ has obtained Tom Petty's death certificate -- which still does not identify his official cause of death. 

The document, filed with L.A. County, says Petty passed away at 8:43 PM on Oct. 2 at UCLA Santa Monica. 

He's listed as a songwriter and a musician -- who worked in the field for 40 years. 

As we first reported ... Tom was rushed to the hospital after he'd gone into full cardiac arrest and was found unconscious and not breathing. He was eventually taken off life support, and died Monday.

He was 66.