Two escaped convicts from Arizona and a woman who accompanied them kidnapped an Oklahoma couple and gunned them down so they could steal their camping trailer, prosecutors said Monday as they released chilling details about the group's crime spree.

The murder and carjacking charges against John McCluskey, Tracy Province and Casslyn Welch provided a clearer picture of their time on the run and showed how the fugitives turned to killing as they became increasingly desperate.

McCluskey told an FBI agent after being captured last week that he killed Gary Haas with a single shot near the temple, then fired three times to kill Linda Haas, according to a criminal complaint.

When the fugitives noticed blood was dripping from the trailer, they doused it with liquor to set it ablaze on a dirt road before heading to Wyoming.

U.S. Attorney Kenneth Gonzales said all three defendants could face the death penalty if convicted of killing the Tecumseh, Okla., couple.

The Haases, both 61, were traveling to Pagosa Springs, Colo., for a camping trip and were simply "two people on vacation who happened to be at the wrong place at the wrong time," Gonzales said.

Province's account to investigators drives much of the narrative disclosed Monday by authorities. After being arrested in Wyoming, he was taken to Amarillo, Texas, where he met FBI and state police agents who drove him to Albuquerque to retrace the fugitives' journey and document sites of events.

The criminal complaint filed Monday said the fugitives saw the couple at a rest area along Interstate 40 in eastern New Mexico Aug. 2, three days after authorities say Welch helped the men escape from the Arizona State Prison in Kingman.

The three were tired of traveling and sleeping in a car they had stolen in Flagstaff, Ariz., and decided "it would be a good idea to target someone driving a camper or trailer," the complaint says.

McCluskey and Province followed Linda Haas from the trailer to her truck and forced the couple at gunpoint to drive while Welch followed in the car.

Gary Haas suggested the three could leave him and his wife with the 32-foot trailer and take the truck. But McCluskey parked the vehicle in a remote area of New Mexico's Guadalupe County, ordered the couple into the camper and shot them, leaving the bodies inside, the complaint says.

McCluskey drove to a gas station in Santa Rosa and gave money to Province to purchase fuel, according to the complaint. He couldn't do it "because he was covered in blood."

That's when Welch noticed blood leaking from the trailer door. She cleaned up much of it, but Province told FBI agents he saw brown stains at the bottom of the door and on the ground below.

McCluskey drove onto a dirt road to find a place to abandon the trailer. While Province unloaded the Haases' dogs and dumped food for them, Welch and McCluskey poured liquor onto the trailer's floor and fixtures, set it aflame and left.

"Before leaving the area, they made sure that the fire had taken and was burning well," the complaint said.

The three drove the truck and stolen car to Albuquerque, where they bought brake fluid and paper towels to wipe down the truck "in hopes of eradicating or concealing their fingerprints," the complaint says. The vehicle was found two days later at a shopping center.

McCluskey's fingerprints were recovered from plastic wrapping left inside the truck, and investigators determined blood smears found on the truck matched one or both victims.

Province asked McCluskey and Welch to take him to Yellowstone National Park, so they drove him there. Province, 42, was arrested Aug. 8 in Meeteetse, Wyo., and has been returned to Arizona.

After the last confirmed sighting of McCluskey, 45, and Welch, 44, on Aug. 6 in Billings, Mont., the cousins were captured at a campground near Springerville, Ariz., on Thursday. Authorities said McCluskey expressed regret at not having killed the U.S. Forest Service ranger who led to their capture.

Gonzales said efforts were under way to extradite McCluskey, Welch and Province to New Mexico.

Asked at a news conference Monday if New Mexico would become the first place to prosecute the three for their crime spree because it is the location of the most serious charges, Gonzales said, "That's certainly our position."

The trio also face charges in Arizona including kidnapping, armed robbery and aggravated assault with a deadly weapon. Unable to locate a getaway vehicle Welch had stashed in the desert, McCluskey, Province and Welch kidnapped two tractor-trailer drivers using handguns Welch had obtained for the escape, the complaint said.

After driving to Flagstaff, the three took a vote on whether to kill the drivers. McCluskey was in favor but Province and Welch voted to release them unharmed.

A third escaped convict, Daniel Renwick, split from the rest of the group after the jailbreak. He was arrested Aug. 1 in Rifle, Colo.