Russ Jack waits for the word about his missing daughter. The search for two… (Irfan Khan / Los Angeles…)
As the search for two missing hikers in Orange County's rugged backcountry drags on, authorities on Wednesday said they have been forced to examine worse-case scenarios.
So far, though, investigators said they have found no evidence of foul play or any indication that what was supposed to be a casual day hike by a couple of teenagers was actually a diversion and that the two might have gone elsewhere.
Lt. Jason Parks of the Orange County Sheriff's Department said there is nothing so far that undermines the belief that the youths, who attended high school in Costa Mesa together, are lost in the southern Orange County hills.
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Investigators, though, said it is possible that the youths were injured and cannot walk out.
Scores of investigators from agencies across the region Wednesday afternoon continued to comb through the brush near Holy Jim Canyon, where Kyndall Jack, 18, and Nicholas Cendoya, 19, were last heard from.
Authorities said the terrain and the forgiving cloud cover gives searchers reason for hope and that, barring a catastrophic injury, they should be alive.
The pair came to the area Sunday for a hike and called authorities that evening for help, but the cellphone they were using died. In the call, they said they were about a mile from their car. The car was later found parked near a trailhead.
Even though days have passed, authorities remain hopeful about their chances: The weather conditions are favorable, and the two didn't have medical issues or require medication, although the pair -- who are said to be outgoing and athletic but not experienced in hiking -- could be struggling with the rugged terrain, steep slopes and tall brush.
"It sounds like they're fit, they've got good tennis shoes," said Capt. Jon Muir of the Orange County Fire Authority. "We hope for the best."
Authorities also warned volunteer hikers – who have shown up by the dozens – to be cautious as they venture into the backcountry.
In a statement released by the Sheriff's Department, authorities said individuals who want to contribute to the effort should "be prepared, be safe and have a plan."
"When hiking in wilderness areas, be prepared for the unexpected," the statement said.
Jack's father told reporters early Wednesday that dozens of friends and family were still combing the area.
"At this point, everybody's still upbeat, optimistic about finding the kids in good shape and alive," Russ Jack said.
Russ Jack said that about 4:15 a.m. "little sparks" were spotted on a hillside, "like a dead lighter trying to get somebody's attention."
"It ended up being nothing," he said.
Russ Jack ended the brief interview with a message for his daughter: "Kyndall, I love you."
Bloodhounds picked up Jack's and Cendoya's scents early Monday and again late Monday night, officials said.
Tuesday afternoon, rescuers combed through a 2-mile arc from the hikers' car, focusing efforts on where the dogs last found the scents.
The rocky, tree-shaded dirt trail the pair took leads to a waterfall, a popular 2.8-mile round trip hike popular with day hikers.
Its difficulty is listed as moderate to serious on a U.S. Forest Service website.
Jack and Cendoya, however, "did not keep to the trail," authorities said.
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