Patrol Inspector Augustin De La Pena was shot and killed when he intervened in an assault at a restaurant in Rio Grande City, Texas, at approximately 7:00 pm.

He and another inspector were at dinner when a mentally ill man entered and began to argue with the owner. As the man attempted to leave he was confronted by Inspector De La Pena and a struggle ensued in which Inspector De La Pena was shot in the stomach. He continued to struggle with the suspect, and as he grew weak from blood loss, he shot and killed the suspect.

Inspector De La Pena was transported to the hospital at Fort Ringgold where he died at 1:00 am on August 3rd, 1925.

Inspector De La Pena had served with the United States Border Patrol for two years. He was survived by his wife and nine children. He is buried in Rio Grande City, Starr County.