James Austin Kellis, 36, of Springfield, Ore., is considered an endangered missing person, according to the Lane County Sheriff's Office.

BLUE RIVER, Ore. -- A ground and air search is under way for a man who took a city bus to the foothills of the Cascade Mountains Sunday, stopped at a resort to ask for a sip of water and hasn't been since since.

James Austin Kellis, 36, of Springfield, Ore., is considered an endangered missing person, according to the Lane County Sheriff's Office. He is described as mentally delayed and may not have taken medications in the past two days, according to the sheriff's office.

His family reported Kellis missing to the Springfield Police Department on Monday. He was last seen wearing gray slacks, black shoes and a gray T-shirt with "Jesus saves" on the front. Kellis is 6-foot-4 tall, 295 pounds with blue eyes and brown hair.

Kellis took a Lane Transit District bus from Springfield to the Blue River area on Sunday, Sept. 13, something he has done before, the sheriff said. He was last seen at 4 p.m. Sunday at the Holiday Farm Resort, 54455 McKenzie River Dr., where he requested a drink of water. He offered to pay for the water before leaving. The resort staff don't recall any signs that Kellis was in distress, the sheriff's office said.

Kellis has not returned home and his whereabouts are currently unknown. Contact the Lane County Sheriff's Office at (541) 682-4150 if you have seen him.