India, Aug. 17 -- Hayden Panettiere, the actor best known for her roles in Heroes and Nashville, has died at the age of 36.

Panettiere's father, Skip, announced her demise in a statement provided to ABC News Sunday.

"It is with profound sadness that we share the tragic passing of our beloved Hayden. She was 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," his statement said.

Law enforcement sources told TMZ that police responded to an incident involving Panettiere on Sunday, and an investigation is ongoing.

While her cause of death has not been publicly revealed, a source close to Panettiere told TMZ that she had complained of back pain...