TUCSON, Ariz. – A U.S. Border Patrol agent shot and killed an armed suspect Friday about 10 miles south of downtown Tucson, authorities said.

The shooting occurred as two agents conducted a standard surveillance effort known as sign cutting in which agents search for footprints in the desert, said Art del Cueto, president of the Tucson Sector Border Patrol union.

It’s unclear how the agents encountered the suspect and companions, but agents are known to patrol the desert area near the Pascua Yaqui reservation in Pima County.

“Agents recovered multiple weapons and no injuries to the agents involved have been reported,” Border Patrol spokeswoman Nicole Ballistrea said.

The shooting took place near residential neighborhoods. Authorities said the suspect killed was a man, but his name wasn’t immediately released.

Neither agent was hurt, according to authorities.

Ballistrea said agents continued to search for others who fled the scene.

Officers from the U.S. Customs and Border Protection Office of Air and Marine had just finished a media demonstration in Nogales near the Mariposa Port of Entry when they responded to the shooting.

The FBI was named the lead investigative agency with CBP’s internal affairs also looking into the death.