The Navajo Division of Public Safety may ask the Navajo Tribal Council for more than $500,000 to pay for expenses incurred in two separate searches for two suspected cop-killers and to pay for any future manhunts, a Navajo police spokesman said Monday.

The search was called off in part because of the financial burden the manhunt was putting on the Navajo tribe, but tribal authorities are still determining exactly how much last week’s search cost.

Navajo Nation police Chief Leonard Butler called off the search Sunday morning, only hours after Navajo special weapons and tactics teams discovered fresh tracks and heard a noise that sounded like a gunshot. Butler said the search may be on hold for at least a week to give his officers a chance to rest, but said the financial strain had also been "part of the equation."

Regular patrols in the Montezuma Creek, Utah, area will be upgraded to protect people living on the Navajo reservation, according to a statement issued by the Navajo Department of Law Enforcement.

Butler and many other authorities believe the tracks and gunshot are evidence that Alan "Monte" Pilon, 30, of Dove Creek and Jason Wayne McVean, 26, of Durango are hiding in the deep brush along the San Juan River. The two men have eluded authorities for 46 days after allegedly shooting Dale Claxton, a Cortez police officer, and wounding two sheriff’s deputies May 29. A third suspect, Robert Mason, 26, of Durango, was found dead of a self-inflicted gunshot wound June 4 near Bluff, Utah, after allegedly wounding a sheriff’s deputy.

Navajo Nation police Sgt. Tyrone Benally said the Division of Public Safety is still tallying officer overtime expenses, vehicle mileage costs and other miscellaneous charges incurred during the Montezuma Creek manhunt.

The division will likely ask the Navajo Tribal Council to approve a blanket sum to cover any additional searches that may arise, Benally said. That amount could easily be more than $500,000, Benally said.

Benally said the Navajo Division of Public Safety spent $116,000 during the search near Bluff, Utah, after a San Juan County, Utah, sheriff’s deputy was wounded.

More than 60 SWAT team members scoured the riverbanks Saturday night and a search dog followed a new set of tracks Sunday morning, Butler said, but the dog later lost the tracks due to poor air circulation on the riverbank.

Butler said the dog, a border collie, had also become distracted by a group of cattle that had started running near it. Border collies have been bred to herd cattle.

Benally said the majority of police had left Montezuma Creek, but it would still be difficult for Pilon and McVean to leave the area unnoticed.

"This week there’s no one up there, but that’s not to say that a van could just pull up and someone could take them back to Durango," he said.

Benally said the Navajos would work on a plan for use with the San Juan County, Utah, Sheriff’s Office if new reliable information surfaces indicating that the two suspects are in the Montezuma Creek area.

The search for Pilon and McVean has focused on a section of the river seven miles west of Montezuma Creek since June 28, when a 9-year-old girl reported seeing two men wearing camouflage and carrying assault rifles trying to steal a water truck. Since then, Navajo SWAT teams twice have spotted two men and repeatedly gotten within 20 yards of them before being stopped by the dense vegetation.

In all of those encounters, the searchers have been unable to determine if the men are Pilon and McVean. Even if they had identified the two suspects, Butler said his men will not shoot unless they feel they are in immediate danger.

"They have no shoot-to-kill orders or anything like that," he said.