Rescuers fear two missing climbers may have fallen into a half-mile deep glacial crack while trying to descend Mt. Hood, officials said Monday.

The body of the third climber, Kelly James, was found in a second snow cave uncovered by crews Sunday near the spot located by cell phone signals traced to him.

Monday's recovery operation was taking longer than usual because searchers had been directed to thoroughly map out the area of the mountain where the climbers were last seen and get as much evidence as possible while they're up there, said Hood River County Sheriff Joe Wampler in an afternoon press conference.

"Things are going good, but it's taking a lot longer than we thought," Wampler said. "I've asked the team to conduct the best investigation they can while they're there today to determine what may have happened to the other climbers."

The rescue effort has been hampered by the treacherous, crevasse-riddled terrain on the mountain, he said.

Search and rescue teams were scouring the area of the mountain commonly known as "the gullies" — because of its tendency for avalanche and other snow activity — in their hunt for two of the three climbers that have been missing for more than 10 days.

"If we don't find them, I think we're going to have to start poking in the snow and do an avalanche-type search," Wampler said. He said he's been worried about the fate of the climbers since "Day 1."

The press was also warned to respect the privacy of the families, and told they would no longer speak to the media at all if they continued to get 3 a.m. phone calls asking for interviews.

"So long as the family's privacy is respected, they will make themselves available when we have these established press conferences," said Capt. Mike Braibish of the Oregon National Guard. "You must respect the privacy of the families. That is essential."

James' brother, Frank, said Monday that while he has not yet seen the body, rescuers described a ring on the man's hand bearing the climber's initials, which, he said tearfully, "has led me and our family to conclude that the climber found in the cave yesterday was my brother, my brother Kelly."

The body was brought down from the mountain Monday. Frank James and relatives of the two other climbers said the families are grateful for the rescue efforts and are keeping hope alive.

"This is a difficult day for all three families. Our hope is that Kelly, Brian and Jerry would all be rescued safely," Frank James said, reading a statement from the families aloud. "We're persuaded that Kelly has been found but I feel that I have two other brothers still on the mountain.

"As Christians, we find peace that Kelly is with God. Kelly always told us that he felt closest to God when he was on the mountain. That is what drove him to climb and we find enormous comfort in knowing that he lifted off that mountain from the place that he loved and doing something that he loved very, very much."

Earlier Monday, Wampler said there was a non-working cell phone filled with water found with the body.

James placed a four-minute distress call to relatives on Dec. 10 just below the summit. The body was found Sunday and was frozen, indicating James was dead for some time.

"It's real frustrating. We don't like big mysteries like this that last a long time," Wampler said at the noon news conference. "But a lot of things have happened over the past two nights and days. We've gotten a huge amount of information … really, it's kind of narrowed a lot of things down."

The weather was cooperating Monday for searchers as they prepared to again head up the 11,239-foot Mount Hood on Monday to continue their search. Crews were going to be dropped from helicopters to the ground to study the climbing equipment found officials believe was left behind by the missing men.

"We're real sad about one of our results but we still have two missing climbers," Wampler said. "We're going to keep looking for them. Our search has narrowed from totality around Mount Hood to basically the area in which they found the caves and now the area directly below that."

Wampler said teams would focus on possible descent routes on Eliot Glacier and Cooper Spur, relatively lower levels of the mountain, in case the other two got down that far. That area is commonly known as "the gullies," with inclines of 60 percent and a 2,500-foot fall. Wampler said searchers would scour that area by air.

"It's too dangerous for us to put ground crews in there and probably will be over a period of time," Wampler said. "Maybe we'll get a glint of something, but we're going to try ... the minute things stabilize and we can get in there with electronic detectors, probes, we will do that.

Pete Hughes of the sheriff's office said earlier that there are still people in gully crevasses that have never been recovered.

The three climbers had been missing for 10 days, before James' body was found.

James' mother, Lou Ann Cameron, told The Associated Press she did not want to talk about her son and referred questions to the sheriff's office.

"They're a mess — imagine yourselves trying to hear some news," Wampler said of the climbers' families.

"We failed them, we literally failed them. But we did our best … there's still a chance ... and we're going to keep going because of it, for the other two" climbers, he added.

Finding a 'Needle in a Haystack'

On Sunday, rescuers dropped search teams near the mountain's 11,239-foot summit from a CH-47 Chinook helicopter flown by pilots who had served in Afghanistan and Iraq. The pararescue team members scaled 300 feet down the nearly vertical face of the northeastern face of the mountain to reach a snow cave that was spotted from the air earlier in the day.

Near the first snow cave, helicopters had spotted rope that had been intentionally laid out in a Y-shape, which climbers often use to indicate their location. There also was an ice spike, a piece of foam sleeping pad, one wool glove and footprints, apparently headed up the mountain, Wampler said.

The body was found in a second snow cave near the first, about 300 feet below the summit. It was not known if any gear was in the second cave.

"The guys that found that thing [snow cave] was like [finding] a needle in a haystack," Wampler said.

Braibish told FOX News on Monday that search teams will continue their effort until the sheriff calls off the search. Until then, they'll follow the clues the climbers seem to be leaving them.

"What every little piece [of evidence] that we pick up helps us do is zero in and refine our search," Braibish said. "We still look at this as a search-and-rescue mission and every little bit of information we pick up helps us figure out where to look."

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Rescue teams didn't lift the body off the mountain Sunday because they ran out of daylight and didn't want to jeopardize the safety of the crew with the extreme cold and darkness. Temperatures have reached 18 degrees below zero near the summit at nighttime.

The daring rescue operation began when a helicopter spotted the Y-shaped rope formation in the snow early Sunday, Hood River Detective Sergeant Gerry Tiffany said. Rescuers say climbers sometimes use that formation to signify, "Yes, we're here."

Searchers dug through the first cave to ensure no one was there and took the equipment. The second cave with the climber's body was found a short time later.

It was not immediately clear which cave was occupied first, or why or when the climber, or climbers, decided to move from it.

Weather conditions have been harsh since the three were reporting missing, with heavy snow and wind gusts of up to 100 mph. The snow stopped Saturday, but wind of up to 50 mph blew the fresh snow, hampering visibility.

There has been no word from climbers James, Brian Hall or Jerry "Nikko" Cooke since Dec. 10 when James made a distress call to family members. A cell-phone tower picked up a signal from James' cell phone on Tuesday that appeared to have originated from the vicinity of the snow cave.

Survival effort Greg Davenport said it's not very encouraging the two climbers haven't tried to signal rescuers, especially if they're above the tree line on the mountain.

"It's very disturbing to me they haven't made an attempt to signal the aircraft," Davenport said. "It wouldn't have taken much to come out and use some sort of improvised shiny device … there was aircraft all over that mountain yesterday."

He added: "That is a very important need they have to meet."

Dwight Hall, father of missing climber Brian Hall, gulped back tears Sunday and thanked rescuers for their efforts, adding "there's no reason to have anything less than high optimism for a successful outcome."

At the airport, friends and family members of the missing climbers put their hands on one of two Blackhawk helicopters preparing to join the search and prayed. Frank James, brother of Kelly James, said of the helicopter pilots: "We're the cheerleaders for these guys."

FOXNews.com's Liza Porteus and The Associated Press contributed to the report.