GREENVILLE, S.C. (AP) — Actor Hayden Panettiere died from an accidental overdose of several drugs, including fentanyl, a coroner in South Carolina said Tuesday.

Panettiere, 36, was found unresponsive in an apartment in Greenville, South Carolina, on Aug. 16. Her on-and-off boyfriend Brian Hickerson and his brother Zach Hickerson were at the home.

According to a statement from the Greenville County Coroner’s Office, a combination of fentanyl and its chemical byproduct, as well as the anti-anxiety medication alprazolam, a muscle relaxer and a drug used to treat major depression and other serious mental health disorders, were found in Panettiere's system.

The office did not release further details from the autopsy report of the one-time child star.

Asked for comment on the coroner's report, Kasey Kitchen, a publicist for the family, told The Associated Press that “the investigation is still ongoing and the case is complex."

Greenville Police confirmed Tuesday their investigation into Panettiere's death is continuing.

Paramedics came to Panettiere's apartment after a 911 call. Over 40 minutes of CPR and other advanced resuscitation efforts were performed before she was declared dead. No signs of trauma that could have led to her death were found at her autopsy, Greenville County Coroner Mike Ellis said in a statement.

The police report released after her death mentioned a list of medications Panettiere was taking, but the names of the drugs were redacted.