The GBI is conducting an investigation into the death of an inmate at the Forsyth County Jail.

Melissa Ponce, 28, of Tucker, died Nov. 20, about three hours after she was arrested on suspicion of DUI, Forsyth sheriff’s office spokeswoman Stacie Miller said in a news release. Ponce was found unresponsive in a holding cell about 6:30 a.m., Miller said.

Deputies served her breakfast about 30 minutes earlier, according to the release, and saw no signs that Ponce required medical attention. Three jail nurses and deputies performed life-saving measures, including giving Ponce a dose of Narcan and using a defibrillator while they waited for EMS to arrive, Miller said. Narcan is a prescription medicine used to treat a suspected opioid overdose.

The woman was pronounced dead at the scene.

The sheriff’s office’s initial investigation “suggests Ms. Ponce ingested an illegal narcotic prior to being incarcerated at the Forsyth County Jail,” Miller said.

Her body was taken to the GBI Medical Examiner’s Office for an autopsy. Miller said the sheriff’s office is conducting a parallel investigation into the jail death.