BLUFF, Utah – Authorities on Sunday scaled back a massive manhunt for two suspected killers believed to be in the redrock canyons of the Four Corners region – a historic hideout for fugitives.

Searchers conceded that the two men may have never been in the Bluff area, and they planned to move the search center back to Cortez, Colo., Monday.

"It’s a very good possibility that they broke up and went their separate ways," Dolores County, Colo., Sheriff Jerry Martin said.

Cortez is where the manhunt began May 29 after three suspects allegedly riddled a police car with automatic weapons fire, killing a police officer who pulled them over in a stolen water truck.

The three fired off as many as 500 rounds at pursuing officers, wounding two, before fleeing on foot into the desert.

Hundreds of police and National Guardsmen converged on Bluff when one of the fugitives, Robert Matthew Mason, 26, of Durango, Colo., was found near here Thursday at a makeshift camp, having apparently shot himself.

Authorities thought Mason’s suspected companions – Alan "Monte" Pilon, 30, Dove Creek, Colo., and Jason Wayne McVean, 26, Durango, Colo. – were nearby. But they now concede they have no evidence the suspects ever made it into Utah.

Martin said the operation would be cut back by 30 percent as officers return to their jurisdictions in Utah and Colorado to continue following up leads and double-checking locales to where the suspects were initially thought to have fled.

The men vanished despite being sought by a huge contingent that has at its disposal a fleet of helicopters, high-tech spy equipment and Navajo Indian trackers.

Although there is little vegetation in the desert area, it is full of deep sandstone canyons, caves and abandoned mines, which have often been used by others to hide from the law.

"It’s the perfect location for tourists or people who want to hide," said Margaret LaBounty, who owns the Rock Speaks art gallery with her husband, John.

Butch Cassidy and the Sundance Kid hid out in southern Utah during breaks from robberies. In 1923, a Ute Indian outlaw eluded San Juan County posses after allegedly shooting at a sheriff. He was eventually killed.

Hollywood has also used the magnificent redrock buttes in the region as a backdrop for dozens of movies, such as John Ford’s classic, "The Searchers," in which John Wayne looks for his niece (Natalie Wood) who had been abducted by Indians.

"Most of the residents in this town have been in one movie or another," LaBounty said. "(The ongoing manhunt) would make a better movie than most of those filmed here."