U.S. Immigration and Customs Enforcement says the pilot program began Tuesday with the departure of 131 Mexicans. The flights are scheduled to run twice a week through Nov. 29 from El Paso, Texas.
The flights are not voluntary, unlike a previous effort to deport Mexicans arrested by the Border Patrol during Arizona's summer heat.
The U.S. government pays for the flight. The Mexican government pays to get people from Mexico City to their hometowns. Passengers include those with criminal records as well as non-criminals living throughout the United States.
The experiment comes as often-violent Mexican border cities along the U.S. border are overwhelmed with deportees.