ARCADIA (CBSLA.com) — One of two teenage suspects shot by an off-duty U.S. Customs and Border Protection officer Friday night — who authorities say they were trying to rob — has died from his injuries.

A 15-year-old boy was pronounced dead at 5:34 a.m. Saturday at a hospital, the Los Angeles County Sheriff’s Department reports. A 14-year-old boy who also suffered gunshot wounds is expected to survive.

A third teen suspect, a 14-year-old boy, was in custody following the incident, which was reported at 8:13 p.m. Friday near First Avenue and Colorado Boulevard, according to LASD, which is investigating the shooting.

The officer was not shot although he did suffer some bruising to his face and head during the attack but his injuries were treated at the scene and did not require further medical attention, authorities said.

The man works at San Francisco International Airport and lives in Arcadia, officials said.

The officer was walking along the sidewalk on First Avenue, just south of Colorado Boulevard, when he was attacked from behind by the three teenage boys, LASD said.

One of the suspects hit the officer in the head several times while another pointed a handgun at the officer and demanded his property, LASD said.

“The victim thought the subjects were going to rob and shoot him so he retrieved his department issued handgun,” Deputy Caroline Rodriguez said. “The victim shot at the subjects in an effort to defend himself.”

The suspect with the handgun, the 15-year-old boy, and another suspect, one of the 14-year-old boys, were struck by the gunfire while the third suspect ran away when the shooting started and was not hit, according to Rodriguez.

The suspects’ names were not released because they are juveniles.

In a statement, the CBP wrote:

“CBP Office of Professional Responsibility is working closely with the lead agency and will fully cooperate with the investigation. CBP stresses honor and integrity in every aspect of its mission, upholding its officers, on or off-duty, to the highest standards.”

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