Actress Hayden Panettiere, who rose to fame as a teenager on NBC's "Heroes" and later starred as a country-music ingenue on ABC and CMT's "Nashville," was found dead Sunday afternoon inside an apartment complex in Greenville, South Carolina. She was 36.

Greenville police and EMS crews responded to the Judson Mill Lofts on Easley Bridge Road at approximately 1:51 p.m. after an acquaintance called 911 to report a woman in cardiac arrest, according to dispatch audio obtained by TMZ. Paramedics administered advanced cardiac life support, including chest compressions and cardiac medication, but were unable to revive her. She was pronounced dead at 2:32 p.m.

The Greenville Police Department said the preliminary investigation turned up no signs of foul play or suspicious circumstances. The Greenville County Coroner's Office was scheduled to perform an autopsy Monday to determine an official cause and manner of death.

PRELIMINARY FINDINGS HAVE NOT INDICATED ANY SIGNS OF FOUL PLAY OR SUSPICIOUS CIRCUMSTANCES.

Dispatch audio referenced the possibility of an overdose, though authorities have not confirmed that as a factor in her death, and toxicology results typically take weeks to return. It remains unclear why Panettiere, who lives primarily in Los Angeles, was in Greenville over the weekend. Her "Nashville" co-star Charles Esten had performed at The Foundry at Judson Mill — the same complex where she was found — two nights earlier, on Friday, though it isn't known whether the two events were connected, according to Live 5 News.

A Career That Started at Age 11

Panettiere began acting as a child, landing a recurring role on "Guiding Light" before she was a teenager. She broke out globally in 2006 as cheerleader Claire Bennet on NBC's superhero drama "Heroes," delivering the show's signature catchphrase, "Save the cheerleader, save the world," to a generation of fans. She later spent six seasons, from 2012 to 2018, as aspiring country star Juliette Barnes on "Nashville," a role that had her recording and performing original music.

In recent years, Panettiere had spoken candidly in interviews about a prolonged struggle with alcohol and opioid addiction, as well as postpartum depression following the birth of her daughter in 2014, checking into treatment programs on multiple occasions and describing her recovery as an ongoing process. She is also the older sister of actor Jansen Panettiere, who died suddenly in 2023 at age 28.

Tributes from fans and former castmates began circulating online within hours of the news breaking Sunday night, remembering her as one of the most recognizable young stars to come out of the mid-2000s television boom.

The Greenville County Coroner's Office is expected to release results from Monday's autopsy in the coming days, which should offer the first official word on how Panettiere died.