SUNLAND PARK, New Mexico -- A U.S. Border Patrol agent who tried to stop some people believed to have crossed the border illegally shot and killed one of them Monday after the man pulled a gun and opened fire, authorities said.
Two agents approached a group four people about a mile from U.S.-Mexico border and chased one of them who took off running, New Mexico State Police said.
"At some point during the foot pursuit, the suspect fired a weapon at the two Border Patrol agents," state police spokesman Ray Wilson said in a statement.
One of the agents shot back, hitting the man, who died at a hospital. No agents were hurt during the shooting in Sunland Park, New Mexico, a suburb of El Paso, Texas.
The three other people in the group were arrested, a Border Patrol spokesman said. It's unclear what charges they face.
The agent's name was not released, and police were still working to determine the deceased man's identity.
The CBP's Office of Professional Responsibility is conducting an internal investigation.
The FBI also is investigating. Albuquerque FBI spokesman Frank Fisher declined to say which agency would make a final determination about the agent.
Federal authorities blocked off the crime scene, closing a main road in Sunland Park and stretching crime tape between their patrol vehicles.
An auto shop and a car dealership on either side of the street were closed.
This story has been corrected to show that the shooting happened Monday.