The protests came as firefighters in El Paso, Texas, say they discovered the bodies of four migrants—including two children—who died attempting to cross the Rio Grande along the U.S.-Mexico border. The deaths came just days after 10 undocumented immigrants died from heat exposure and asphyxiation after they and dozens of others were crammed into the back of a sweltering tractor-trailer as part of their journey to enter the United States from Mexico. They were found in a Wal-Mart parking lot in San Antonio, Texas.