The remains belonging to the 24-year-old were located in the town of Plymouth in Amador County Thursday, and the identity was confirmed Friday by a forensic odontologist.
Gabe disappeared on Jan. 26, where she was last seen leaving the Antioch home of her former boyfriend, Marshall Jones.
Her car was found in Oakley but there was no sign of her.
Investigators say they determined Jones drove to the area where Alexis' remains were found in the hours following her disappearance.
Jones was killed in a Seattle suburb in June when police moved in to arrest him.
Officials say a press conference will be scheduled for early next week.
Stay with ABC7 News on this developing story.
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