A 19-year-old California hiker is recovering from severe dehydration after being rescued Wednesday evening in the Cleveland National Forest, southeast of Los Angeles.

Nicholas Cendoya and his friend Kyndall Jack, 18, were last heard of on Easter Sunday, when they vanished during a weekend hike. 

Early Thursday morning the search for Jack resumed, aided by a sheriff's helicopter with infrared sensors.

Cendoya was discovered in heavy brush by another hiker shortly before 8 p.m. Wednesday and airlifted to a hospital. He was talking to paramedics but struggling to answer questions about what had happened and where Jack might be.

"He was extremely confused and disoriented," said Orange County Sheriff's Lt. Jason Park.

Sheriff's investigators planned to talk to him at length once he was recovering at Mission Hospital in Mission Viejo. They hoped to get more direction on where to look for Jack, who was hiking with Cendoya Sunday when the pair made a 911 call from a dying cellphone and set off the search.

The hiker who came across Cendoya went for help and found a firefighting training crew not involved in the search that just happened to be nearby, Park said.

They found Cendoya about a half-mile south of where much of the search had focused. He was surrounded by so much vegetation that the helicopter rescue crew had trouble keeping track of him once they found him.

"When the rescuer was lowered he lost sight of him," said Division Chief Kris Concepcion of the Orange County Fire Authority. "That's how thick the brush was."

Several dozen searchers with help from helicopters had been combing the rugged hills of Trabuco Canyon in the national forest.

Two volunteers got lost themselves and had to be airlifted out Wednesday afternoon. They were searching the area because the Sunday 911 call was traced to a nearby cell tower, Orange County Fire Authority Capt. John Muir.

Muir said earlier that Cendoya and Jack's "probability for survival is good" with mild weather both day and night.

The two were believed to have gone off trail near Holy Jim Trail, a tree-lined dirt path along a creek that leads to a waterfall and is popular with day hikers.

In the 911 call, they said they were about a mile from Jack's car, which was parked at a trailhead, but rescuers expanded the search when they weren't found nearby.

Jack's mother drew a message on the car's dusty windshield that read: "Kyndall — we r looking wont stop love you mom," and signed it with a heart.

"When you're disoriented because you're out of breath and tired and you think you're one mile away, you could be potentially three or four miles away," Muir said Wednesday afternoon. "There's a lot of ground to cover."

Based on reporting by The Associated Press.

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