Police said they have no idea what happened or where she has been.
Duer had been last seen a week ago Sunday.
Her family said she moved to the area about a year ago and went to school at Cal Poly Pomona.
They also said she'd been telling them about a possible stalker for the past year and a half, though they have no idea who he may be, and Duer's landlord said on the day she disappeared she received a mysterious phone call.
- Get more local news headlines from Los Angeles
- Have a news tip? Send your tips, video, or pictures