The L.A. County Coroner has begun the autopsy on Sage Stallone, according to TMZ.
Sources for the website say the autopsy will be completed on Sunday.
According to investigators, there were no signs of foul play or trauma in the death of the 36-year-old actor, son of Sylvester Stallone and Sasha Czack.
Additionally, Sage could have been dead for three to four days prior to the discovery of his body, law enforcement sources reportedly told the website.
As previously reported on AccessHollywood.com, Sage was found unresponsive in his Los Angeles home Friday by an employee and a relative, and police arrived and confirmed he was dead, Assistant Chief Coroner Ed Winter said.
"Sylvester Stallone is devastated and grief-stricken over the sudden loss of his son," publicist Michelle Bega said in a statement. "His compassion and thoughts are with Sage's mother, Sasha."
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