A police officer was shot to death as he sat in his patrol car during a traffic stop Friday, igniting a chase that carried into the rugged desert canyons near the Colorado-Utah border.

Officer Dale Claxton, 45, was killed about 9:45 a.m. after pulling over a flatbed truck that had been reported stolen out of La Plata County, east of Cortez, Police Chief Roy Lane said.

"As he attempted to stop the vehicle, the suspects opened fire on his patrol vehicle. He was killed instantly at the scene," Lane said. "The vehicle fled from there."

About two minutes later, a mile from the original shooting, two Montezuma County sheriff's deputies were also shot while trying to stop the men. Jason Bishop was grazed in the head, and Todd Martin was shot in the left arm and right knee.

Cortez City Manager Bill Ray said Bishop was "up and around" Friday afternoon, while Martin was listed in satisfactory condition at Southwest Memorial Hospital.

Despite several roadblocks, the three male suspects, clad in camouflage, managed to elude authorities as they drove northwest on U.S. 666 into sparsely populated landscape of pinon pine and juniper trees.

Along the way, the three ditched the flatbed truck and stole a construction truck, which they eventually abandoned near the Hovenweep National Monument north of the Navajo Indian Reservation. Two automatic weapons were recovered by police, but Ray said he did not know if the men were still armed.

A helicopter from Mesa Verde National Monument and a private airplane conducted an aerial search, and about 40 law enforcement officers from the region swept the area on the ground in both Utah and Colorado.

In Utah, the San Juan County Sheriff's Office implemented a full-scale manhunt in Cross Canyon, using dog teams and resources from the Monticello and Blanding police departments, said Sheriff Mike Lacy.

The National Guard and the FBI were standing by with night-tracking equipment if the search went past sundown.

"It's very rugged country out there," Ray said. "There's a lot of brush and primitive roads."

The area, which attracts thousands of tourists each year in search of backcountry experience, has been celebrated in the novels of Tony Hillerman and Edward Abbey.

The chase along U.S. 666 prompted the small town of Pleasant View to virtually shut down.

Highway 666 has been criticized by some religious groups for its name. The groups say there is a connection between an inordinate number of crashes on the desolate byway and the number 666. In the Bible's Book of Revelation, 666 is the number of the beast, or the devil.

Claxton, who had been with the police department for three years, lived about two miles outside of Cortez, a town of about 7,100, - with his wife and two children, ages 11 and 13, Lane said.