Authorities have detained two men believed to be connected to the fatal shooting of two suspected illegal entrants southwest of Green Valley Friday morning.

The men were found separately near a campsite about a half-mile south of where the shooting occurred, said Dawn Barkman, a Pima County Sheriff's Department spokeswoman. Investigators found three firearms at the campsite and continue to look for additional suspects. They expect to make arrests soon, she said.

At 5 a.m. about five miles south of Duval Mine Road on Caterpillar Trail (view map by clicking images to the right), unknown shooters opened fire on an extended cab pickup truck traveling north with 23 illegal entrants, killing two and injuring another.

A man and woman were found dead at Duval Mine Road a few hundred feet from where the bullet-riddled extended cab pickup truck they were in came to rest on Caterpillar Trail, said Pima County Sheriff Clarence Dupnik. Another suspected illegal entrant injured in the fatal shooting - a man with gunshot wounds to his ankle and torso - was found in the desert north of where the shots were fired. He was taken to a Tucson hospital with non-life-threatening injuries.

None of the illegal entrants in the pickup saw the shooters, Dupnik said.

The shooting could have been an act of border banditry and the assailants may have been seeking narcotics, said Dupnik. An illegal entrant who was in the truck told investigators that when shots rang out, the driver yelled into the darkness that the group had no drugs, Dupnik said.

Armed ripoff teams, or bajadores, have become increasingly brazen in the past two years in their attempts to steal loads of drugs and people from smugglers, especially in the Interstate 19 corridor between Nogales and Tucson.

The group's ill-fated journey began about 8 p.m. Thursday night from Sasabe, Sonora when 23 people from three families who told investigators they were from Chiapas, Mexico loaded into a white Ford extended cab pickup with a camper shell, Barkman said. The group included three children under 7 years old, including a 1 1/2 year-old baby.

They were headed north on the dirt Caterpillar Trail about five miles southwest of the Duval Mine Road when they were peppered with gunfire at about 5 a.m.

Officials haven't said how many shots were fired but at least a dozen bullet holes were visible in the windshield and front of the truck.

The truck continued traveling north until it failed a few hundred yards south of Duval Mine Road. The 21 suspected illegal entrants who survived the shooting walked to Duval Mine Road carrying the two victims. At 5:10 a.m a passerby saw them and called 911, Barkman said.

Two or three human smugglers - or "coyotes" - are still at large.

Investigators spent Friday morning combing the area by foot and helicopter, inspecting the pickup and interviewing the witnesses, who will be held in custody by the Pima County Sheriff's Office until they are no longer needed for the investigation, Barkman said.

U.S. Border Patrol agents were called in to assist the Sheriff's Department in the investigation and met the survivors.

"They are extremely scared," said Gustavo Soto, Border Patrol Tucson Sector spokesman. "They just had two people die that were part of their group. " The route the group appeared to have taken -coming northeast through the west desert corridor and angling toward I-19 south of Tucson- is a popular one for drug and human smugglers.

The route bypasses a Border Patrol checkpoint at Kilometer 48 on Interstate 19, and then allows smugglers to take entrants to Tucson and Phoenix. "They are trying to stay off the main roads to avoid being detected," Soto said.

In this case the illegal entrants were headed for Tucson, and then perhaps to Los Angeles, officials said.

This is the second deadly ambush on vehicles carrying illegal entrants in Pima County in the past two months.

On Feb. 8, in the far northwest side of Tucson near Silverbell Mine Road, unknown assailants opened fire on a truck carrying between 15-20 illegal entrants, killing three (a Guatemalan man, and a Mexican man and woman) and wounding two others.

The Sheriff's Department isn't near a solution in that case, Dupnik said.

"The situation on the border, particularly in the Tucson Sector, has reached crisis proportions," Dupnik said.

The Tucson Sector has seen increased violence between human smugglers as Border Patrol and the National Guard ratcheted up enforcement along the border, said senior Shannon Stevens, a Border Patrol spokeswoman for the Tucson Sector.

Historically that violence was directed at Border Patrol agents, but now smugglers have become motivated to steal from one another as it has become more difficult to transport people and narcotics into the United States, she said.

"It's kind of a double-edged sword," she said.

The tragedy is a symptom of a failed immigration system that forces people coming to work into the desert and into the hands of smuggling rings that control the routes, said Kat Rodriguez, coordinating organizer for Coalición de Derechos Humanos, a Tucson-based immigrants' rights group. Increased enforcement has forced human smugglers into drug smuggling routes, which has caused the in-fighting, she said.

"It's so terrible," Rodriguez said. "It must have been a terrifying experience to have guns open fire and people dying."

∫ Contact reporter Dale Quinn at 629-9412 or dquinn@azstarnet.com, or Brady McCombs at 573-4213 or bmccombs@azstarnet.com

For more Arizona news, visit www.azstarnet.com or www.azfamily.com.

©The Arizona Daily Star, 2006