David Allen Soto, 18, from Wildomar, was last seen leaving the Elsinore High School campus at about 8 a.m. Tuesday. School staff conducted a search of the neighborhood and called authorities when they couldn't find Soto.
Soto has autism and takes medication for schizophrenia. Authorities say he has the mental capacity of a 12-year-old.
Soto has wandered away before, but never for this long. The teen's mother, Anna Espinoza, said her son likes to go exploring.
"I don't think he really understands the compromising position he puts himself in...that he's that much in danger," said Espinoza.
Soto is 6 feet tall, 140 pounds with brown hair and brown eyes. He was last seen wearing a long-sleeve Lakers hooded sweatshirt with blue Levi pants and black tennis shoes.
As the search continued into day three, Riverside County sheriff's search teams were out looking for Soto in and around the edge of the Cleveland National Forest. But it could be a tough search since Soto may not want to be found.
"The volunteers also know that he likes to hide sometimes," said Lt. David Knudson with the Riverside County Sheriff's Department.
It's for that reason that just this week, New York Sen. Chuck Schumer proposed placing tracking devices on children with autism. It's an idea Espinoza supports.
"I think that with children with autism and delays, like David, that would be a great idea for us to be able to know, family members and maybe as well as authorities, to be able to locate him that way," said Espinoza.
If you have any information about Soto's whereabouts, you're urged to contact the Riverside County Sheriff's Department's Lake Elsinore Station at (951) 445-7951.