She was 36 years old.

Details about Panettiere's untimely death were not publicly released.

Panettiere was best known for her roles in "Nashville" and "Heroes."

ABC News reported:

Actress Hayden Panettiere has died, her representative confirmed to ABC News. She was 36 years old.

"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," her rep said in a statement.

Further details surrounding Panettiere's death were not immediately available.

TMZ also reported that Hayden Panettiere passed away earlier today.

Per TMZ: Hayden Panettiere, best known for her roles in "Heroes" and "Nashville," has died at 36, TMZ has learned.

"Sources with direct knowledge tell TMZ … Hayden pass away earlier today. We're told she and Brian Hickerson flew from Los Angeles to the south Saturday. We're told Brian Hickerson's family is aware and sources say "it's a sad situation,"" TMZ reported.

Hayden Panettiere previously revealed she struggled with alcoholism and postpartum depression.

Panettiere's younger brother, Jensen, died in 2023 at the age of 28.

Hayden Panettiere has a young daughter with her ex-fiancé, Wladimir Klitschko.