Officers, managers, dispatchers and drivers at Golden State Transportation in Los Angeles were charged with running an immigrant smuggling scheme that transported and harbored tens of thousands of illegal immigrants throughout the Southwest. Federal agents raided the bus company's downtown bus terminal Monday and charged 32 people, including the company president. The two-year investigation, dubbed "Operation Great Basin," centered on Golden State's operations in California, Arizona and Colorado, reported the Los Angeles Times. The scheme allegedly began in 1996. Attorney General John Ashcroft said Golden State sold blocks of bus tickets to smugglers to transport immigrants from Mexico border communities to cities like Los Angeles and Denver. Between 50 and 300 migrants were allegedly shuttled from city to city each day last year, reported the Times. Those indicted are charged with illegally transporting migrants within the United States, not with smuggling people across the U.S.-Mexico border. An indictment unsealed in federal court in Tucson, Ariz., revealed that passengers were picked up at Golden State bus terminals in secluded areas, often hidden and loaded onto buses just before departure. The company's buses arrived and departed after midnight to escape police detection and routes were often changed to circumvent checkpoints, officials said. Golden State is 51% owned by Sistemas Internacional de Transporte de Autobuses Inc., a Dallas-based subsidiary of Greyhound Lines Inc. Greyhound has no involvement in the investigation.