Heroes and Nashville star Hayden Panettiere’s death officially ruled accidental by police

The death of US actress Hayden Panettiere has officially been ruled accidental by law enforcement authorities in South Carolina, bringing an end to the local police investigation into her fatal drug overdose.

The Heroes and Nashville star passed away on August 16 at the age of 36 after being discovered unresponsive inside a private residence in Greenville, South Carolina.

Following an extensive inquiry into the circumstances surrounding her death, the Greenville Police Department confirmed on Tuesday that it has formally closed its case.

"Based on the Medical Examiner's determination and the findings of the investigation, Hayden Panettiere's death has been ruled accidental," the department said in an official statement.

Last month, the Greenville County Coroner's Office determined that the former child star died from the toxic effects of a lethal combination of drugs, including fentanyl, Xanax, the prescription muscle relaxant methocarbamol, and the anti-psychotic medication quetiapine.

Hayden Panettiere sadly died of an accidental overdose in August (Photo by Jon Kopaloff/Getty Images)

First responders dispatched to the scene initially treated Panettiere for cardiac arrest, with subsequent autopsy findings confirming there were "no signs of trauma" contributing to her passing.

The presence of illicit fentanyl—a synthetic opioid significantly more potent than morphine that has driven America's devastating overdose crisis—prompted federal interest.

The US Drug Enforcement Administration (DEA) reportedly joined local investigators in probing the supply chain and circumstances leading up to the tragedy.

While the municipal police inquiry is now officially concluded, it remains unclear whether the federal inquiry into the source of the narcotics remains active.

According to a police incident report from the day of her death, Panettiere’s ex-boyfriend, Brian Hickerson—who previously served jail time after pleading guilty to domestic violence charges involving the actress—was present alongside his brother Zack when paramedics and emergency personnel arrived at the residence.

A local investigation has now been closed, however the status of a federal probe into the source of the narcotics remains unknown(Charley Gallay/Getty Images)

Panettiere first rose to global prominence as a child and teen actress, gaining worldwide fame portraying cheerleader Claire Bennet on NBC’s sci-fi phenomenon Heroes before delivering a critically acclaimed, multi-season run as country music sensation Juliette Barnes on Nashville.

Throughout the latter years of her life and career, the actress spoke with profound candor about her personal battles with severe substance abuse, alcoholism, and postpartum depression.

Her untimely death at 36 adds another tragic chapter to Hollywood's ongoing struggle with synthetic opioid overdoses, sparking an outpouring of grief from former co-stars, creative peers, and legions of fans across the globe.

Tributes have continued to pour in honoring Panettiere's vast artistic legacy, with friends and advocacy organizations remembering her not only for her memorable on-screen performances, but for her honesty in addressing the realities of mental health and addiction.