MIAMI, Feb 10 (Reuters) - U.S. federal agents have taken into custody six commercial pilots and two airport workers, all from Venezuela, on immigration-related offenses, officials said. Another suspect in a case being investigated by local and federal agencies including the Immigration and Naturalization Service is still at large. The U.S. Attorney's Office in Miami said in a statement issued late on Saturday that six of the suspects were charged with having fraudulent stamps in their passports indicating they were legal permanent residents with authorization to work -- which would enable them to obtain a Social Security card and seek employment. Two others were detained by INS officials on unspecified immigration charges. "This office is strongly committed to identify, arrest and prosecute individuals who commit fraud in order to work illegally in areas affecting domestic security and airline safety," said U.S. Attorney Guy Lewis. James Goldman, INS assistant district director, was quoted by the Miami Herald as saying the suspects apparently sought only to gain illegal entry and employment in the United States, but he added that the scheme was "frightening" in light of the Sept. 11 airborne assaults on New York and Washington. "Here we are battening down all airports, putting passengers through rigorous security checks and yet here we have pilots flying our jets who entered this country fraudulently without undergoing any of the usual security checks," he said. Two of the pilots worked for American Eagle, two for a cargo aircraft company and one for an executive jet company, while the sixth pilot's place of work was not given. The airport workers had jobs as a mechanic and an aircraft fueler. Marty Heires, a spokesman for American Eagle (AMR), a regional affiliate of American Airlines, told the Miami Herald that the airline fully cooperated with authorities in the investigation. If convicted, the defendants face a maximum term of imprisonment of 10 years for possession of fraudulent documents and five years for making false statements.