Law enforcement agents spent Tuesday combing the desert where a Border Patrol agent was shot earlier in the day, but declined to release details at an afternoon press conference, though they believe there was more than one shooter.

Agent Nicholas Ivie, 30, was fatally shot about 1:30 a.m. in rugged terrain in a remote area seven miles east of Bisbee and five miles north of the U.S.-Mexico border.

He and two other agents were responding to a tripped sensor near mile marker 352 on Highway 80. One agent sustained non-life threatening gunshot wounds to the ankle and buttocks and was airlifted to a hospital where he was in stable condition Tuesday afternoon. The third agent was not injured. It is unknown whether the agents returned fire.

Authorities declined to comment on whether anybody is in custody or if any weapons or other evidence were collected at the scene, saying it is too early in the process. They said processing the scene could take days.

No arrests have been made, but authorities suspect that more than one person fired at the agents.

Ivie was a native of Provo, Utah, and joined the U.S. Border Patrol in January 2008. He worked as an emergency medical technician before joining the Border Patrol, said his brother-in-law, Todd Davis. He served a two-year mission with The Church of Jesus Christ of Latter-day Saints in Mexico City after high school.

He lived in Sierra Vista, and was assigned to the recently dedicated Brian A. Terry Border Patrol Station in Naco. Ivie’s desire to help others, and his love of the outdoors and riding horses led him to the Border Patrol, where he served on the horse patrol unit, Davis said.

He leaves behind a wife and two young daughters.

Commander Jeffrey Self said Ivie died in the line of duty while protecting the nation against those who threaten the public’s way of life. His death strengthens the resolve to enforce the rule of law and bring those responsible to justice, said Self, who is the commander of Joint Field Command of Arizona with Customs and Border Protection.

“Many of the CBP family received a call at 2 o’clock this morning and it has been a long day for us, but it has been longer for no one more than a wife, whose husband is not coming home, and it has been longer for no one more than two children whose father is not coming home,” he said at Tuesday’s press conference in Naco.

Joint investigation

The area near the shooting is scattered with houses, trailers and ranchettes. Mesquite trees and creosote bushes dot the landscape, with a mountain range nearby to the west.

The U.S. government has put thousands of sensors along the border that, when tripped, alert dispatchers that they should send agents to a particular location.

The agents were fired upon in a rugged hilly area about five miles north of the border as they responded to an alarm that was triggered on one of the sensors, said sheriff’s spokeswoman Carol Capas. It is not known whether the agents returned fire, she said.

James Turgal, special agent in charge for the Federal Bureau of Investigation’s Phoenix Division, said the shooting incident demonstrates the danger that law enforcement agents face along the Southwest border everyday. Turgal said the FBI’s Phoenix Division and the Cochise County Sheriffs Office are conducting a joint investigation.

“We have deployed Phoenix Division evidence response teams ... to process the crime scene, which may take some time, and I have pledged all FBI resources from across the country to assist in support of this investigation,” he said.

The scene of this shooting is in the general vicinity of the January 2007 incident in which Border Patrol Agent Nicholas Corbett fatally shot Francisco Javier Dominguez Rivera, an illegal immigrant from Mexico, who was entering the United States. Corbett was charged but the case was later dismissed after two trials that resulted in hung juries.

In December 2010, Border Patrol Agent Brian Terry, who began his career at the Naco Station, was fatally shot while on patrol near Rio Rico. His murder is linked to Operation Fast and Furious, a program in which federal law enforcement agencies knowingly allowed the trafficking of illegally purchased weapons into Mexico.

Robert Heyer, cousin of Agent Terry and Chairman of the Brian Terry Foundation, said in a statement Tuesday that the family extends its heartfelt prayers and condolences to family of the Border Patrol agent who lost his life and to the family of the agent who was shot and has been hospitalized.

Officials are urging anyone with any information about Tuesday’s shooting incident to call 1-877-872-7435.

Includes information from the Associated Press.