GREENVILLE, S.C. — New details have emerged about the final moments of actress Hayden Panettiere's life, with dispatch audio reportedly referencing an "overdose" and "cardiac arrest" around the time she was found unresponsive at a residence in Greenville, South Carolina, on Sunday.

Police officers and EMS personnel responded to reports of an "unresponsive female," later identified as 36-year-old Panettiere, at approximately 1:50 p.m. local time Sunday, according to the Greenville Police Department, which confirmed the details to People. Authorities were alerted to the medical emergency through a 911 call placed by a friend of the actress, according to TMZ, which cited law enforcement sources. The identity of the caller has not been publicly disclosed.

According to TMZ's reporting, first responders attempted to resuscitate Panettiere using advanced cardiac life support, a set of emergency medical procedures that, in addition to standard CPR, can include specialized medications, breathing tubes and continuous heart rhythm monitoring. Despite those efforts, including chest compressions administered by paramedics, Panettiere was reportedly pronounced dead at 2:32 p.m.

Dispatch audio obtained by People captured officials discussing the terms "overdose" and "cardiac arrest" around the time of Panettiere's death, offering the clearest indication yet of what first responders may have encountered at the scene.........

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