A helicopter chartered by the family of James Kim trails equipment over the Big Windy Creek drainage about 30 miles west of Grants Pass as part of their search for the San Francisco man. Searchers found a pair of Kim's pants and spotted other articles Tuesday. (Sol Neelman/The Oregonian)

GRANTS PASS -- Searchers combing a cold, rugged canyon for the father of two missing for 12 days planned to lower a rescuer into a chasm today to examine something else he may have left behind.

Although they wouldn't elaborate on the item, search officials and family hoped both discoveries will lead them to Kim, a high-tech editor who left his stranded family four days earlier to seek help. But other rescue experts said finding the pants may signal that Kim was in the late stages of fatal hypothermia.

Searchers found the pants one mile below a Bureau of Land Management road in the Big Windy Creek drainage, which runs toward the Rogue River. They also found Kim's footprints and scuff marks another mile downstream.

A second item -- possibly more clothing belonging to Kim -- was found deep in a chasm but searchers couldn't get to it before dark Tuesday. Searchers also found "other items" that may belong to Kim, Lt. Gregg Hastings of the Oregon State Police said Tuesday night, but were waiting for verification they were his.

"We'll continue searching until we find Mr. Kim," said Josephine County Undersheriff Brian Anderson. "We are operating under the assumption that he is alive. ... This is frustrating. ... We are so close. We are treating the search like we're looking for our own family member. We're not going to give up."

More than 100 ground searchers ended their quest at dark Tuesday because of the rugged terrain. An Oregon Air National Guard helicopter equipped with night-vision and heat-sensing equipment continued flying a five-mile stretch of the drainage 30 miles west of Grants Pass.

James and Kati Kim with their two daughters, 4-year-old Penelope and 7-month-old Sabine, had been missing since Nov. 25 after driving south from Portland to visit the southern Oregon Coast. A helicopter found Kati Kim and the girls Monday waving an umbrella near their stranded car. But James Kim had struck out on foot two days earlier seeking help.

James Kim left the family at 7:45 a.m. Saturday, telling his wife he'd be gone for four hours. He never returned to the car, where the family had burned the vehicle's tires to keep warm after it ran out of gas.

Searchers said Kim hiked three miles back up the BLM road and then -- for what reason they do not know -- walked into the rugged Big Windy Creek drainage. Searchers believe he was wearing at least two pair of pants.

Hastings said the pants could be an indication of Kim trying to mark the path. "I think that would be a smart thing to do," Hastings said.

But some cold-weather experts said the pants are an indication that perhaps Kim was suffering from the late stages of hypothermia.

Dr. Cameron Bangs, one of the state's leading hypothermia experts, said it is common for someone stranded for a long time in cold weather to start "paradoxical undressing."

Bangs said the term refers to how when someone's core temperature drops below 90 degrees, the body's cooling systems begin to fail. The result, Bangs said, is that warm blood moves toward the skin and a person begins to feel hot.

"You become confused and behave in a strange manner," Bangs said. "You feel too warm and you start shedding clothes. It's a bad sign. It's a bad sign that he's been out there for too long without much equipment."

Anderson did not disclose what officials thought the item in the chasm might be.

Kim's family secluded themselves Tuesday but issued a statement expressing gratitude for the search efforts.

"The family wishes to express their deepest, heartfelt gratitude for the tremendous outpouring of love, concern and assistance to find the family," the statement said. "We are overjoyed that Kati, Penelope and Sabine are safe and sound, largely due to James Kim's remarkable efforts to ensure the safety of his family in this desperate situation."

One searcher, a 38-year-old Jackson County sheriff's deputy, was injured in a fall Tuesday and had to be airlifted to a Medford hospital. Anderson said the injuries weren't life-threatening.

Searchers scoured the steep terrain from Monday night until darkness fell Tuesday. Elevations in the area reached to about 3,500 feet and temperatures dipped into the 20s.

Bob Harrison of the Eugene Mountain Rescue was part of the crew that found James Kim's tracks. Working a shift that lasted from 10 p.m. Monday to noon Tuesday, Harrison and four other trackers said the conditions in the canyon were nothing short of treacherous.

"It was very rough going," Harrison said. "Very slow. We didn't go near as far as we thought we could."

The crews had to cover lots of steep ground that was littered with downed trees, heavy brush and the occasional sheer-faced cliff that would pop up in front of them. Mostly, crews had to continue crossing and re-crossing Big Windy Creek when obstacles prevented them from getting by.

Even in daylight, the searching conditions were treacherous. Harrison added that the helicopters hovering above couldn't see the search crews who were wearing bright orange vests.

Searchers bring in a tracking dog Tuesday to join the hunt for James Kim of San Francisco in the Big Windy Creek drainage of the Rogue River (Carlos Avila Gonzalez/The San Francisco Chronicle)

While in the drainage, searchers tried to look under debris to see if they could find James Kim. "Someone who is cold and is going to hole up under protective logs, we look for that sort of thing," Harrison said.

There were about 100 people searching Tuesday, along with three helicopters chartered by Kim's family and one from Josephine County. Two rafts also were launched into the Rogue heading toward Black Bar Lodge.

At nightfall, the Air National Guard copter took to the skies. Anderson said officials planned to monitor the length of the drainage through the night and into this morning near its outlet into the Rogue River for any signs of the missing man.

Missed turnoff

The Kims were headed to Gold Beach Nov. 25 but missed a main route there and decided to take a shortcut west of Grants Pass, friends and authorities said.

At first it was only raining as they drove up Bear Camp Road but snow began falling as they got higher in the mountains. Kati Kim told a friend Monday that the road was pretty bad and at one point she and her husband had to get out to remove rocks from the road. They soon realized they weren't going to make it over the mountain and decided to drive back to a lower elevation to get out of the snow.

The Kims drove 15 miles down a BLM side road before stopping for the night because they were out of the snow. They parked, leaving the engine running so they could use the heater.

"They thought they could spend the night and somebody would find them in the morning," said Ryan Lee, the Portland friend who talked with Kati Kim after her rescue Monday. "But then, when they woke up, it was snowing quite heavily. They were stuck."

The Kims ran the engine of their 2005 Saab station wagon for three days to power the heater until the car ran out of gas, Hastings said.

For seven days, the parents rationed baby food and crackers for their children, drank melted snow water and tried to keep warm. The adults at first ate berries but then gave them up for fear of getting poisoned, Lee said.

Before long, the car battery had also gone dead. Then they huddled together in the car, burning all their tires to stay warm.

That's when James Kim decided to venture out Saturday to try to find help. At one point after her husband left, Kati Kim ventured away from the car to look for help.

But, weak from hunger, she quickly determined that she was unable to carry both girls and returned to the shelter of the car, according to an account she gave her mother and father, Sandra and Phil Fleming of New Mexico.

Kati Kim nursed both girls throughout the ordeal.

Elizabeth Suh and Mark Larabee of The Oregonian contributed to this story.