CORTEZ – Amid the night-vision goggles and Black Hawk helicopters fixed with inferred lenses that have been used to seek three fugitives in the rugged canyons northwest of Cortez, a group of Navajo trackers leading the search are acting decidedly low-tech.

Crouched low, they travel on foot, looking for the drop of blood, the footprint, the overturned rock or snapped twig that could lead to the capture of three murder suspects.

But the Navajo Nation team looking for Jason McVean, Robert Mason and Alan Pilon in the maze of drainages that makes up Cross Canyon is frustrated.

It’s been six days since the suspects were last seen; they should have been caught by now. The Navajo trackers say 99 percent of the time they find their man within 36 hours.

Tracking is in their blood, something they have done for hundreds of years.

But this is no ordinary search.

"There are so many little drains and coves and each one is a good hiding place," said Montezuma County Sheriff Sherman Kennell. "It is hard to track them through that stuff, particularly if the suspects are familiar with the area and have long training with concealment.

"It is not a normal situation as far as chasing a fugitive in the field."

It is also hot out there, with unrelenting 95-degree temperatures and a beating sun. Trackers wear thick, black, long-sleeved shirts and pants over body armor and Kevlar helmets, exacerbating the heat. And the gnats and other nasty bugs in the canyon are fierce, searchers say.

"Our bodies ache and our eyes are tired from tracking," said Sgt. Timothy Lane, a tracker with the Navajo Police District in Tuba City, Ariz. "It is hot out there."

And then there is the fact that they are looking for cop-killers believed to be carrying automatic weapons and described as having anti-government sentiments. Kennell said of the 500 rounds they fired after being pulled over by police and the car chase that followed, hardly a bullet was aimed at civilians, even though they had plenty of opportunity to do so.

"They are still armed and we know when we find them they are going to shoot," Lane said. "If one of them sees us before we see them we are going to get hit. The stress is high."

Four years ago, a Navajo tracker was killed by a fugitive he was searching for during a hunt east of Page, Ariz.

"It’s like hunting a dangerous animal out there," said Capt. Bill Hillgartner, commander of the Navajo police district in Shiprock. "That is how we look at it."

So they travel slowly, inching up the canyon.

Of a 10-man team in the field, two will be on point and two at the rear, semi-automatic rifles drawn, so the six trackers can concentrate on looking for clues.

So far the team has found two sets of fresh footprints matching those of the suspects at two locations in the canyon, in both instances heading north. Each time they have called in reinforcements – about 200 of whom have been available – but the trail has always grown cold.

Mario Joe, a member of the Navajo tribe and tracker with the Shiprock police district, said the fugitives are experienced with concealment, walking on the sides of their feet to hide tracks, stepping on brush that doesn’t stay crushed and hopping from rock to rock instead of on the dirt.

"They would be difficult to track even in good conditions," Joe said. "But this area is so thick that even if we are on track it hard to see."

Joe said Navajos have a long tradition of producing trackers, dating back hundreds of years. In the vast expanse of the largest Indian reservation in the country, occupying 25,000 square miles, Joe said the bond to the land is great and provides much room for training.

"The Navajo tradition teaches you to respect everything around you," Joe said. "If something is out of place, you know.

"Rocks that have been sitting in the same place for hundreds of years don’t just move."

Fresh tracks can be differentiated from old ones by looking at how much wind and water has eroded them, he said.

About 50 trackers from four Navajo police districts have participated over the six days, making about two searches a day.

Hillgartner, a non-Indian who has had experience with other police forces around the country, calls the Navajos among the best trackers in the world. He is confident that if the fugitives are still out there -- and he believes the are – his men will find them.

"We certainly wouldn’t abandon this in mid-stream," Hillgartner said. "It’s a brotherhood out there and when something like this goes down with a fellow officer, you don’t even have to call for our assistance – we will be there.