Garrett Reid, the son of Philadelphia Eagles head coach Andy Reid, died in August of an accidental heroin overdose.

Northampton County District Attorney John Morganelli held a news conference Thursday to release details of the investigation and coroner Zachary Lysek confirmed the cause of death was "acute opiate 'heroin' toxicity."

Garrett Reid died Aug. 5 at the age of 29. He was found dead in a dorm room at Lehigh University, site of the Eagles' training camp.

The younger Reid had battled substance abuse for a few years, spending time in jail as a result, and Andy Reid had mentioned the drug problems in the immediate aftermath of Garrett's death, saying in a statement his son had "lost the battle that has been ongoing for the last eight years."