On the evening of December 27, 1933, Patrol Inspectors Bert G. Walthall, Louis A. Smith, and Curtis D. Mosely were patrolling the international boundary near Cordova Island at El Paso, Texas. Cordova Island is not in fact an island, but Mexican territory left on the north side of the Rio Grande River when the river changed its course. The boundary here was an imaginary line and a person could step across from one country to another.
At about 8:45 p.m., the officers noticed two men cross the line with sacks on their backs and depart in a waiting automobile. The officers attempted to stop the car by blowing their horn but the smugglers only increased their speed. After a chase of a couple of blocks, the patrol car overtook the smugglers and the smugglers pulled over to the side of the road. Before the patrol car could be stopped, it had arrived along side the smugglers' car, about 10 feet to the left of it. Inspector Mosely was driving, Inspector Walthall was sitting beside him, and Inspector Smith was in the back seat. When the patrol car stopped, Officers Walthall and Smith alighted from the right side. They were met by a blast of rifle fire from the smugglers which instantly killed Inspector Walthall and wounded Inspector Smith. Inspector Mosely had gotten out of the car on the left side and opened fire on the smugglers whose car was then in motion. Inspector Mosely continued shooting with his rifle and pistol until his weapons were empty and then turned his attention to his fellow officers.