SALEM, Oregon (CBS SF) — A massive search was underway in the Oregon wilderness for a hiker from Sebastopol, who has been missing since Wednesday.

Riley Zickel went into the Mt. Jefferson Wilderness area on Wednesday for an overnight hike, but had yet to return by Saturday, according to Marion County sheriff’s officials.

Parents of the 21-year-old graduate from Analy High in Sebastopol contacted authorities, who in turn, launched the search. Zickel’s vehicle was found near a trail head.

Marion County authorities have deployed some 34 searchers and K-9 on the ground and called in several agencies, including the U.S. Forest Service, the Army National Guard and the Civil Air Patrol to assist.

According to officials, Zickel is an experienced hiker and had adequate food and supplies when he left on Wednesday. They say he may be carrying a cell phone, but no signal has been intercepted because it may be turned off. A specialized mountain rescue team is climbing Mt. Jefferson just in case Zickel decided to hike the 10,495-foot summit.

There are 190 miles of trail in the Mt. Jefferson Wilderness, an area popular with backpackers because of its vast number of hiking options. Searchers remain optimistic because the weather has remained above freezing.

Zickel left Sebastopol to attend college in Oregon and lives in the Portland area. His parents arrived in Portland on Sunday to help with the search. They were working with sheriff’s deputies, distributing fliers and photos of their son.

“He’s just a dear young man, just a sweetheart,” said longtime friend Carey Caccavo Wheaton of Sebastopol in an interview with the Press Democrat. “We’re all praying for him.”

So far, one person confirmed seeing Zickel on Wednesday. Authorities were asking anyone else who was in the Jefferson Wilderness who saw or had contact with Zickel to call 503-584-7724 or 503-584-SRCH.