TUCSON, Ariz. (AP) -- A U.S. Border Patrol agent who was killed by friendly fire near the Arizona-Mexico border died from a gunshot wound to the head, an autopsy report released Wednesday concluded.
A bullet slug and a bullet fragment were recovered from the body of 30-year-old Agent Nicholas Ivie.
Investigators said Ivie and two other agents responded Oct. 2 to a tripped underground sensor that's designed to detect smugglers and illegal immigrants.
The shooting occurred in the early morning hours in a rugged hilly area about five miles north of the border near Bisbee, Ariz., an area known for drug smuggling.
Ivie approached on foot from the north. The two other agents walked in from the south when Ivie apparently opened fire, eliciting a deadly barrage of return fire from his colleagues.
Ivie was killed. Another agent was wounded; the third agent was uninjured.
The autopsy report doesn't say which agent fired the fatal shot.
Authorities have said the agents were about 20 yards from each other when the gunfire erupted. The FBI has called it a case of friendly fire,
Ivie's death marked the first fatal shooting of a Border Patrol agent since Agent Brian Terry was killed in December 2010 in a firefight north of the Arizona-Mexico with a group of Mexican men who authorities said had come to the United States to rob smugglers as they sneaked marijuana into the country.
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