Death of actress Hayden Panettiere cause of death ruled an accident

(NBC, KYMA) - Actress Hayden Panettiere's death was due to fentanyl and other drugs, according to authorities in South Carolina.

On Monday, the Greenville County Coroner's Office revealed her cause of death was "the toxic effects of fentanyl, 4-ANPP, Alprazolam, Methocarbamol, and Quetiapine."

The Drug Enforcement Administration is also investigating the actress's death.

The "Heroes" and "Nashville" actress was found dead in August at the Greenville County apartment complex where she had been staying.

Police who responded to the scene said there were no signs of foul play.

Panettiere's on-again, off-again boyfriend Brian Hickerson was at the apartment complex at the time of her death and showed authorities what police called a bag of medication she was taking.

She was 36.