In 1949 the Border Patrol seized nearly 280,000 illegal immigrants. By 1953, the numbers had grown to more than 865,000, and the U.S. government felt pressured to do something about the onslaught of immigration. What resulted was Operation Wetback, devised in 1954 under the supervision of new commissioner of the Immigration and Nationalization Service, Gen. Joseph Swing.
Swing oversaw the Border patrol, and organized state and local officials along with the police. The object of his intense border enforcement were "illegal aliens," but common practice of Operation Wetback focused on Mexicans in general. The police swarmed through Mexican American barrios throughout the southeastern states. Some Mexicans, fearful of the potential violence of this militarization, fled back south across the border. In 1954, the agents discovered over 1 million illegal immigrants.
In some cases, illegal immigrants were deported along with their American-born children, who were by law U.S. citizens. The agents used a wide brush in their criteria for interrogating potential aliens. They adopted the practice of stopping "Mexican-looking" citizens on the street and asking for identification. This practice incited and angered many U.S. citizens who were of Mexican American descent. Opponents in both the United States and Mexico complained of "police-state" methods, and Operation Wetback was abandoned.