Actor Hayden Panettiere died from an accidental overdose of several drugs, including fentanyl, a South Carolina coroner said Tuesday.

She was 36.

Panettiere 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.

The Greenville County Coroner's Office said her system contained fentanyl and its chemical byproduct.

It also contained the anti-anxiety medication alprazolam, a muscle relaxer, and a drug used to treat major depression and other serious mental health disorders.

The office did not release further details from the autopsy report.

A family publicist, Kasey Kitchen, said the investigation is still ongoing and the case is complex.

Greenville Police confirmed their investigation is continuing.

Paramedics responded to a 911 call and performed CPR and other resuscitation efforts for more than 40 minutes.

Panettiere was then declared dead.

Coroner Mike Ellis said an autopsy found no signs of trauma that could have contributed to her death.

A police report listed medications she was taking, but the drug names were redacted.

Panettiere became famous in the TV shows "Heroes" and "Nashville."

In her memoir "This Is Me," released in May, she described lifelong scars from early fame.

She also acknowledged addiction to alcohol and postpartum depression after her daughter Kaya was born in 2014.

Her younger brother, actor Jansen Panettiere, died of a heart condition in 2023 at age 28.

She also spoke about her relationship with Brian Hickerson, who was charged in 2020 with multiple counts of felony abuse.

He pleaded no contest to two counts of injuring a spouse or partner.

He served a short jail term, followed by four years of probation.