Published: Dec 15, 2010 5:44 PM EST
Updated: Dec 15, 2010 2:46 PM EST

NOGALES, Ariz. (AP) - The leader of a union representing Border Patrol agents says an agent who was fatally shot north of the Arizona-Mexico border was trying to catch bandits who target illegal immigrants for robbery.

National Border Patrol Council President T.J. Bonner says 40-year-old Brian A. Terry was waiting with three other agents in a remote area north of Nogales on Tuesday when a gun battle with the bandits began.

Border Patrol spokesman Eric Cantu would not confirm Bonner's account, but noted that authorities have four suspects in custody and are searching for a fifth.

The FBI is investigating the shooting and didn't immediately return a call seeking comment Wednesday morning.

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