UPDATE 8/28 3pm: Cassidy Thomas has been found! She was discovered in Missouri where she still is. "The Missouri police will be talking to her before the New York State Police contact us," says Shelly Shoemaker, Cassidy's grandmother.

New York State Police say Cassidy willingly left her home with a friend. Missouri Police checked on her welfare and confirmed she was not coerced and/or forced to leave her residence.

An upstate New York teen has been out of touch for days and her family fears she's the victim of an online predator.

18 year-old Cassidy Thomas was last seen August 25th in Cape Vincent, New York when her family says she left with someone she met online. "A search of her computer shows she's been on several dating sites and out of the blue someone shows up to pick her up," says Cassidy's grandmother Shelly Shoemaker. "We have not heard from her since she left, which is very uncharacteristic. And her phone is now off."

Cassidy has Asperger Syndrome and Shoemaker says she is very naive and can be too trusting. "She does not realize the danger she may have put herself in. Cassidy comes from a small town with a tight knit community. The school superintendent and the Mayor are both concerned."

There are a few details on the person who arrived to pick up Cassidy. A neighbor contacted the family after seeing a 2008ish green Toyota van while planting hay. "It's a green van with out of state plates. I think the plates were white and red. The driver looks semi small, kind of thin, with longer hair," said the neighbor.

Search parties have been organized to look for Cassidy or the vehicle she was seen getting into. "People are going to all the small towns looking for the van and trying to see if she's still in the area," says Shoemaker. "I did receive a call about a sighting in the Ogdensburg area but haven't heard anything from the police yet."

The family has made calls to several different police agencies. "I have contacted 7 different state troopers but we're told we can't file a missing persons report because she's 18, a legal adult, and can come and go as she pleases," Shoemaker explains. "They've taken down the information but with the limited information they don't know where to begin looking."

Cassidy was last seen wearing a brown top and white shorts when she left her home on County Route 4 in Cape Vincent Saturday, August 25th around 2pm. If anyone has seen Cassidy or the van, they are asked to call the New York State Police in Alexandria Bay and ask for Investigator Alex Swenson or contact Shoemaker at 315-778-1264 or message her on Facebook.