Gainesville, Florida -- Investigators are digging for clues in the Tiffany Sessions case, 25 years after she disappeared in Gainesville.
Sessions was 20 years old when she went for a walk near the University of Florida campus and never returned back on February 9, 1989.
On Thursday morning, state and Alachua County detectives announced they know who killed her, but still need the public's help to close the case.
See Also: Tiffany Sessions' mother reacts to break in the case
Detectives believe Sessions was murdered by Paul Rowles, a convicted serial killer. They're now digging up a remote, wooded area, because investigators say this area was one of Rowles' dump sites.
It all comes down to a journal they found in Rowles jail cell last year after he died. On it, the date that Tiffany Sessions was last seen alive.
"It's the biggest lead we've had in 25 years," says cold case homicide detective Kevin Allen.
An orange stick in the middle of the field marks a grave site for one of the women Rowles allegedly killed and then dropped her body here.
"A DNA connection was made in the Beth Foster case and she was found behind the woods here," says Alachua Sheriff Sadie Darnell.
Deputies are hoping they can find Tiffany's body somewhere nearby.
"We believe this to be a dumping site as well for Tiffany," says Sheriff Darnell.
Tiffany's mother, Hilary, believes Rowles is responsible for Tiffany's disappearance, but her family hopes this clue may bring them a step closer to knowing exactly what happened to their daughter nearly 25 years ago.
"She's my only child. I have to know," says Sessions.
Anyone with information is asked to call the Alachua County Sheriffs Office.
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