ORGAN PIPE CACTUS NATIONAL MONUMENT, Ariz. -- On a hot desert morning last week, a group of 20 tourists gathered in the visitor center in Arizona's Organ Pipe Cactus National Monument to attend a mandatory safety briefing before taking a guarded van tour to Quitobaquito springs. The springs is part of the 69 percent of the remote border park west of Tucson that has been closed to the public since Kris Eggle, a 28-year-old law enforcement park ranger, was shot and killed while pursuing drug runners armed with AK-47s in 2002.

Organ Pipe was named "the most dangerous national park" that year and also in 2003 by the U.S. Park Rangers Lodge of the Fraternal Order of Police, before the group discontinued the series. The drastic increase of drug activity on Arizona's southern border since the 1990s has turned Organ Pipe rangers into de factor Border Patrol agents, and spurred state lawmakers to pass several laws cracking down on illegal immigrants within the state.

Since 2009, the park has offered van tours to the springs, as long as rangers armed with rifles go along to protect the visitors. Now, ten years after Eggle's murder, the park's leadership has decided to open up a portion of the closed areas to the public in March, citing improved safety conditions and a big increase in Border Patrol agents in the area.

In the run-up to Tuesday's Republican presidential primary in Arizona, immigration has once again been a hotly contested topic in the state: Mitt Romney in a debate last week praised Arizona's immigration laws as a "model" for the country, while President Obama's Justice Department is suing Arizona to overturn one of those laws, called SB1070. The law--which has not gone into effect because of a federal court order--requires police to check a person's immigration status during stops if there is a "reasonable suspicion" that someone is in the country illegally. It also makes it a state crime to fail to carry immigration papers or for illegal immigrants to solicit work. Drug violence has claimed tens of thousands of lives in Mexico since President Felipe Calderon declared war on the cartels in 2006, but spillover violence has so far been minimal in the United States. Still, Jan Brewer, the Republican governor of Arizona, falsely claimed that beheadings occurred in the Arizona desert in 2010, the same year she signed SB1070 into law. Arizona was also the first state to pass a mandatory E-Verify law in 2007, to ensure employers don't hire illegal immigrants.

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Brewer says the law will help police officers combat drug trafficking and crime, but critics say it will encourage racial profiling and interferes with federal control over immigration. Yahoo News went to Organ Pipe last week to witness the challenges of the border as the presidential candidates debate how best to control it.

'They'll have M14s at hand. Don't be worried.'

"There is a chance we might have to cancel the tour if there's some sort of apprehension in progress," Park Ranger Karl Sommerhauser, wearing a bulky dark green bulletproof vest, told the tourists last week. Sommerhauser had an ear piece curling out of his left ear. "We expect you to take direction from Ken," he said sternly.

Ken Hires, an unflaggingly cheerful park ranger dressed in reassuringly normal-looking tan ranger clothes, bounded to the front of the room. Hires is what's called an interpretive ranger, which means he has no law enforcement duties and does not carry a weapon. ("I spent my five years in Vietnam. Enough shooting," he said later.) Hires explained that some law enforcement officers would be hiding in the hills and closely watching the two-hour nature hike, while another pair of armed rangers would follow the tourists closely from the ground. "They'll have M14s at hand," he told the group. "Don't be worried."

"You might see something interesting off the trail, but please don't go wandering off," Hires continued, explaining that it made it difficult for the rangers to track people from the hills. "Please be respectful that those people are putting themselves on the line for us."

As the group loaded into the vans, one woman from Idaho whispered to her husband: "Does it make you worried? They get chest protections, and we don't get none of them."

Hires, sitting in the passenger side of the van, began talking quickly into his radio to the rangers. He turned to the back and explained: "We operate this as if it were an incident."

"You say there was an incident out there?" a walrus-mustachioed passenger wearing a cowboy hat asked warily.

"We're it," Ken said, to nervous laughter.

'There's nothing normal about Organ Pipe'

Organ Pipe Cactus National Monument, a 330,000-acre, surprisingly green stretch of Sonoran desert populated by barrel, saguaro and organ pipe cacti, spans 30 miles of the U.S.-Mexico border. The park became a corridor for drug runners in the 1990s after border security tightened at major ports of entry and in urban areas, driving human and drug traffickers to rural crossings. Alan Bersin, the Customs and Border Protection commissioner until last year, admitted that the Tucson sector of the border was "out of control" until recently. In 2010, half of all border apprehensions and drug seizures occurred in the Tucson sector, which encompasses much of Organ Pipe.

Drug runners would cut across Mexican Highway 2 through Organ Pipe's dirt roads in a car and then quickly hop onto U.S. Highway 85, which shoots up to Phoenix or Tucson. The vehicles blazed more than 200 miles of unauthorized roads through the park, and rangers found themselves in dangerous, high-speed chases nearly every day. An $18 million, 23-mile vehicle fence put up after Eggle's murder by the Department of the Interior cut down on this vehicle traffic. Now, cartels have had to get smarter, sometimes cutting into the fence, removing it, driving through, and then putting it back together again. Drug runners also started coming more on foot, dropping their packages in designated spots on the highway for someone else to pick up.

The Department of Homeland Security recently put up nine surveillance towers in the park, making it easier for agents to detect this new foot traffic, so the drug runners are now hiding in the hills, where the towers can't see them. (A Border Patrol helicopter operation last year in these hills netted 800 pounds of trash and a whole "herd" of people, according to Hires.) Border Patrol set up a check point on Highway 85 within the park in the past year, which has pushed drug traffickers to the neighboring Cabeza Prieta National Wildlife Refuge and Tohono O'odham reservation, adding as much as four days to their on-foot journeys. "They're very adaptive, more so than us," said Organ Pipe park superintendent Lee Baiza wearily, during an interview with Yahoo News last week.

Baiza said he spends about 80 percent of his time working with Homeland Security and handling border concerns. "There's nothing normal about Organ Pipe," he added.

The superintendent, who took over in 2007, has faced criticism for preventing Border Patrol agents from building new roads in the wilderness areas of the park, which is part of a larger struggle between Homeland Security and national park and land agencies that operate on the border. (More than 85 percent of border property in Arizona is federally owned.) Bob Bishop, a Republican representative from Utah, introduced a bill last year that would waive environmental laws up to 100 miles north of the border, freeing up Homeland Security to build roads through the wilderness to combat illegal immigration and drug running. Bishop criticized the U.S. Fish & Wildlife Service for preventing Border Patrol agents from driving off-road in the Quitobaquito area of the park because of a pond nearby that contains the endangered Sonoran desert pupfish.

"I may care about the pupfish, but I also care about kids getting hooked on illegal drugs that are coming over that border," Bishop told Yahoo News. Drug runners cause more environmental damage to the border by leaving trash, he said, than Border Patrol agents would by building roads.

"Every congressman seems to have his own idea of what we're doing wrong," Baiza said. "The reality is all of that has improved immensely since 2007."

Apprehensions in the park were down last month for the first time in three years, Baiza said. Border Patrol would not release park-specific data, but a spokesman, Jason Rheinfrank, said that the Tucson sector overall saw a 40 percent drop in apprehensions last fiscal year, while the number of agents has nearly tripled since 2000. Illegal crossing arrests over the entire border were at a four-decade low last fiscal year, in part because of the flagging American economy.

On March 1, 46 percent of the park--instead of 31 percent--is scheduled to be open to the public. Baiza cited the increased fencing, number of Border Patrol agents, and technology in the park as the reasons for the change.

'What we are trying to do is retake this landscape'

"The real problem we have with safety is drug dealing, not the people looking for work," Hires said from a loudspeaker system at the front of the van. Three different border patrol agents riding ATVs raced by, waving. "What we are trying to do is retake this landscape so we can all be free to be out here," he added.

Twenty minutes later, the vans arrived at Quitobaquito, where two young men toting heavy M14 rifles were already waiting. The rangers arrived at the springs two hours earlier to scour the area and make sure no one was hiding.

"Please be respectful and don't photograph them," Hires warned. The park service is worried that cartel members would retaliate against the rangers if their faces were publicized. Baiza says Organ Pipe never sends out press releases announcing new ranger hires for the same reason.

The armed park rangers didn't greet the group and stayed about 20 paces ahead on the trail. Hires showed the tourists the endangered Sonoran desert pupfish in the pond (the endangered Sonoran mud turtles were nowhere to be found), and answered questions about the names of different plants and flowers. He explained that the springs has been a crossroads for thousands of years, an oasis drawing thirsty desert-dwellers and entrepreneurial shell traders. The tour ended, and two volunteer rangers stood guard as visitors used the restroom in the bushes before the long van ride back.

"You got to show me your visa," one volunteer ranger joked as people began loading back into the van.

On the way out, Hires pointed out the two park rangers at the top of the hill, green specks on the horizon.

Another border patrol ATV zoomed past the van and stopped the law enforcement park rangers who were escorting the group back to the visitor center. Two brown packages were tied to the back of the ATV.

"See those bundles? Want to guess?" Hires asked. "Marijuana." In 2005, the last year the park released border incident data, Organ Pipe park rangers seized 17,000 pounds of marijuana.

The rangers let out a dog from the back of the SUV, as the visitors craned their necks to watch from the van. The dog jumped out and ran to the bundles. He sat down abruptly and pointed his nose at the packages, then looked back at his masters. "That's the sign," Hires said. The rangers tossed the jubilant dog a toy, and the Border Patrol agent drove off again in the ATV.

"There's been a sighting of a UDA," Hires said a few minutes later, listening to his radio. (UDA means undocumented alien.) "He's sitting next to a trash can which means he's waiting for us to pick him up and give him a ride home. He's given up."

'I feel safer here than in Fresno'

Despite all the excitement on the trip, Hires said he thinks the park is very safe because of the law enforcement rangers and the Border Patrol agents.

"I feel safer here than in Fresno," Hires said after the tour. (He works seasonally in Sequoia and Kings Canyon national park near Fresno, California.)

But visitors--or rather, the people who are choosing not to be visitors--still have concerns. In 2010, visits to the park plunged to a 10-year low of 209,600. Baiza says that when state politicians focus on the dangers of Mexico and the border, fewer people visit the park.

"They come here all petrified," Bonnie Auman, a park volunteer, said. "Then they see all the law enforcement, the Border Patrol."

Bishop, the Utah congressman, said that while the stagnant economy may have significantly deterred unauthorized migrants who are looking for work, he doesn't think it has made a dent in the number of drug runners targeting Arizona. "That's why we need to control the border," he told Yahoo News. "They're not going to be affected by E-Verify and the economy, and the Border Patrol needs to have the ability to battle that."

It remains to be seen whether visitors will be lured back. Hires journeyed to the Quartzsite, Arizona, RV show last month to recruit wary RVers to visit the park. "The No. 1 question: 'Is it safe there?'" he said. "And the second one was, 'Are you open?' People thought we totally closed the place."

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