MYRTLE BEACH, S.C. (WBTW) — Sheridan Wahl, the 21-year-old University of South Florida was reported missing after traveling to Myrtle Beach to visit family — was dropped off at a fire station before her death due to “erratic” behavior, according to Florence County Coroner Keith von Lutcken.

Wahl was dropped off at the Hannah-Salem Friendfield Fire Department along Highway 378 by a man who picked her up near Keith Lane. Lutcken couldn’t go into detail about what the behavior was, but told WBTW investigators tracked down a witness who told them that.

Investigators did take statements from the driver who dropped her off, Lutcken said.

Wahl’s body was found Sept. 21 at the base of the department’s training tower, Lutcken said. The tower is located at the back of the facility. Her body was found about 10 miles from her burned car in Florence County. Authorities haven’t revealed what caused the fire.

Lutcken said Wahl’s body was at the base of the tower for approximately 18 hours. He said the cause was undetermined because there is a 24-hour hole in the timeline of events.

Wahl’s toxicology report showed no illicit drugs or anything of concern in her bloodstream, Lutcken said. He also said there were only minor signs of external injuries and most of the injuries were internal due to a fall.

The manner of death can be changed if new information becomes available, Lutcken said.