Hayden Panettiere's cause of death confirmed by officials

NEW YORK, NY - JANUARY 05: Hayden Panettiere discusses "Nashville" with the Build Series at AOL HQ on January 5, 2017, in New York City. (Photo by Roy Rochlin/FilmMagic)

Hayden Panettiere’s cause of death was confirmed on Tuesday, more than one month after the "Nashville" and "Heroes" star died. 

Hayden Panettiere's cause of death

According to a statement from the Greenville County Coroner’s Office, Panettiere died from a combination of fentanyl and its chemical byproduct, as well as the anti-anxiety medication alprazolam, a muscle relaxer and a drug used to treat major depression and other serious mental health disorders, were found in her system. 

The 36-year-old died on August 16 in Greenville, South Carolina.  

The Greenville County Coroner’s Office did not release further details from the autopsy report.  When asked for comment on the coroner's report, Kasey Kitchen, a publicist for the family, told The Associated Press that "the investigation is still ongoing, and the case is complex."

The Greenville Police Department confirmed Tuesday that their investigation into Panettiere's death continues.

Dig deeper:

The cause of death lines up with TMZ’s report earlier this month that stated that Panettiere likely died after taking an oxycodone pill laced with fentanyl. 

The outlet reported that she had a longtime drug dealer in Los Angeles who allegedly supplied her with black-market prescription drugs, including oxycodone.

RELATED: Hayden Panettiere, who starred in ‘Nashville’ and ‘Heroes,’ dies at 36

Sources told TMZ that the alleged dealer was the target of a Drug Enforcement Administration investigation as authorities worked to determine his relationship with the actress and trace the pill back to its source.

Hayden Panettiere’s preliminary autopsy

Dig deeper:

Last month, Panettiere’s preliminary autopsy results were released and found no signs of trauma contributed to her death. 

"First responders and Emergency Medical Services arrived on scene and located a female in cardiac arrest," the Greenville County Coroner’s Office said in a statement at the time. "EMS personnel initiated advanced cardiac life support measures; however, resuscitation efforts were unsuccessful, and the individual was pronounced deceased at 2:32 PM."

RELATED: Hayden Panettiere's friends and former co-stars share tributes

The Greenville County Coroner’s Office and Greenville City Police Department launched parallel investigations into her death.

"At autopsy no signs of trauma were discovered that would have contributed to the death," the coroner's statement continued.

A preliminary investigation into the death of Panettiere also found no signs of foul play or suspicious circumstances, according to police.

Hayden Panettiere’s legacy

In addition to her roles as Claire Bennet on "Heroes" and Juliette Barnes on "Nashville," Panettiere was also in "Remember the Titans" and, "I Love You, Beth Cooper" as well as Scream IV and VI, among dozens of other credits. 

The winner of three Teen Choice Awards, a Grammy Award nominee and a three-time Golden Globe nominee, Panettiere did her own singing on "Nashville" playing opposite Connie Britton for four seasons on ABC. 

The Source: The information for this story was provided by TMZ, previous FOX Local reporting contributed. This story was reported from Los Angeles.

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