(RIO RICO, Ariz.) -- A border patrol agent was shot and killed late Tuesday in an area 15 miles north of the U.S. border with Mexico, authorities said.
Agent Brian Terry was on patrol when he encountered a group of suspects in the Peck Canyon area near Rio Rico, Ariz., before he was shot, according to a statement from U.S. Customs and Border Protection.
Officials detained four suspects and are still pursuing a fifth. Border patrol agents and local law enforcement officers have been fanning out across the area with K9 teams to track down the suspect.
"Our thoughts and prayers are with the Terry family for their tragic loss," said CBP Commissioner Alan Bersin. "Our commitment to Agent Terry and his family is that we will do everything possible to bring to justice those responsible for this despicable act."
It is unclear whether the suspects were believed to be illegal immigrants or engaged in illicit trafficking or smuggling.
The FBI and Santa Cruz County Sheriff's Office are leading the investigation into Terry's death.
The Arizona National Guard, which presently has 560 troops dispersed along the border to support the Border Patrol, said its members were not involved with the incident.
Terry's murder is the first death of a border patrol agent in the line of duty since July 2009, when Agent Robert Rosas was killed on patrol along the border in southern California.
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