Days after Hayden Panettiere's death at 36, federal law enforcement is reportedly joining the case. As first reported by TMZ on Aug. 19, the U.S. DEA is participating in the multi-agency investigation into the "Heroes" star's Aug. 16 death inside a South Carolina apartment complex. ABC News also confirmed the development.

The other investigating agencies are the Greenville Police Department and the Greenville County Coroner's Office. Panettiere's cause of death has not been released; autopsy and toxicology results could take up to three months. At 1:58 p.m. on Aug. 16, an officer arrived at the Judson Mill Lofts and observed EMS performing CPR on an unresponsive female. Life-saving efforts continued until 2:31 p.m., when death was pronounced.

Brian Hickerson and his brother, Zach Hickerson, called 911. The responding officer spoke first with Zach, who identified Panettiere as his brother's girlfriend. Brian showed police a "bag of medication" the actress was allegedly taking. The officer noted Zach was "very emotional" during resuscitation attempts, while Brian "did not become emotional" until death was declared.

Panettiere's relationship with Brian Hickerson, which began in 2018, involved multiple domestic violence arrests. After a 2020 arrest, Hickerson was sentenced to 45 days in jail, four years' probation, and 52 domestic violence classes after pleading no contest to two felony counts of injuring Panettiere. The pair had recently fueled reconciliation speculation.