India, Sept. 22 -- Hayden Panettiere's cause of death has been confirmed following the actor's sudden death at the age of 36. The Heroes and Nashville star died at her South Carolina apartment on August 16, with authorities now saying that her death was accidental and linked to the toxic effects of several substances, including fentanyl.

The Greenville County Coroner's Office confirmed the findings on Tuesday. Authorities also said there were no signs of trauma while police separately stated that their preliminary investigation had found no indication of foul play or suspicious circumstances.

Here is what is known about Panettiere's cause of death, the circumstances surrounding her final hours, her career, daughter and her public strugg...