The Loudoun County Sheriff’s Office says authorities have uncovered a “document mill” that manufactured hundreds of documents for illegal aliens, and suspect that others are operating in the area. A search warrant executed at a Sterling town house yielded evidence of at least 500 fraudulent documents, the sheriff’s office said. The documents included work visas, driver’s licenses, Social Security cards, permanent resident cards, work authorization cards and photographs of customers. Sheriff’s office spokesman Vincent DiBenedetto said authorities believe other mills are operating and are continuing to investigate.

Three illegal immigrants — Santos Felipe Abrego-Archila, Jose Alfredo Abrego-Archila Jesus Orellana-Mena — and were arrested in connection with the scheme.