Federal agents from the Drug Enforcement Administration have joined local authorities investigating the death of actress Hayden Panettiere.
The Greenville City Police Department in South Carolina is the lead investigative agency, and the DEA is assisting.
The 36-year-old former child star died Sunday afternoon at an apartment complex in Greenville, South Carolina. Responding emergency crews found her in cardiac arrest after her boyfriend and his brother called 911, according to police reports.
Emergency responders performed CPR at the scene, but efforts to revive her were unsuccessful. She was pronounced dead at 2:32 p.m., the coroner’s office said.
Dispatch audio from the call mentioned a possible drug overdose alongside cardiac arrest. An autopsy performed Monday showed no signs of physical trauma. Authorities have not released an official cause or manner of death while they wait for standard toxicology test results, which can take several weeks.
Investigators are looking into her medical history and medications. A heavily redacted police report notes that Panettiere’s boyfriend, Brian Hickerson, handed officers a bag containing her prescriptions when they arrived.
Panettiere had been open about her health and personal struggles. In a memoir published earlier this year, she wrote candidly about her battles with postpartum depression, addiction, and the death of her brother.
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Her former partner, retired Ukrainian boxing champion Wladimir Klitschko, paid tribute to her following the news. The pair share a daughter, Kaya.
“Our family is going through a time of profound shock and grief,” Klitschko posted Tuesday on X. “She built an incredible career through immense talent, while also facing the darker sides of a very demanding industry.”

