Hayden Panettiere died from the “toxic effects” of multiple drugs, including fentanyl, a coroner has confirmed.

The actress, known for her roles in Heroes and Nashville, died aged 36 on August 16 at a residence in Greenville, South Carolina.

Her death was initially reported as a suspected drug overdose.

A spokesman for the Greenville County Coroner’s Office has now confirmed the cause of death to the Daily Mail, saying an autopsy found no signs of trauma that would have contributed to her death.

The spokesman told the Daily Mail: “An autopsy was completed by a Board Certified Forensic Pathologist.

“At autopsy no signs of trauma were discovered that would have contributed to the death.

“The cause of death has been ruled as toxic effects of fentanyl, 4-ANPP, Alprazolam, Methocarbamol, and Quetiapine.

“The manner of death has been ruled accident.

“This case is administratively closed by the Greenville County Coroner’s Office.”

Fentanyl is a synthetic opioid that is significantly more potent than morphine and can be fatal in very small amounts.

Panettiere’s family previously described her as an “incredible light” who brought “immeasurable love and joy to all who knew her”.

Her father, Skip Panettiere, said: “an incredible light and a force of nature who brought immeasurable love and joy to all who knew her – and to the millions who watched her onscreen”.

He also asked for privacy as the family “take time to process this unimaginable loss”.

Panettiere’s former partner, boxer Wladimir Klitschko, said his family was “going through a time of profound shock and grief” following her death.

The couple began dating in 2009 and split in 2018. They share daughter Kaya, who was born in 2014.

In 2018, Panettiere gave Klitschko full custody of their daughter as she struggled with alcohol addiction, opioid use and post-partum depression.

Panettiere rose to fame as cheerleader Claire Bennet in the superhero drama Heroes before taking on the role of country singer Juliette Barnes in Nashville, appearing in the series for six seasons.

Her performance in Nashville earned her two Golden Globe nominations for best supporting actress, while songs she performed for the series appeared 11 times on the US Billboard Hot Country Songs chart.

Her film credits included Bring It On: All or Nothing, Raising Helen, Scream 4 and Scream VI, in which she reprised her role as Kirby Reed.

The actress had previously spoken publicly about her struggles with addiction, revealing that she had battled substance abuse throughout her 20s.

The London Standard has contacted the Greenville County Coroner’s Office for comment.

Frank offers confidential advice about drugs and addiction (email , message 82111 or call 0300 123 6600) or the NHS has information about getting help.