A South African woman originally suspected of having links to terrorist groups but in the end charged only with being an illegal immigrant pleaded innocent in federal court on Friday. Farida Goolam Mahomed Ahmed, 48, faces a possible 15 years in prison and $500,000 in fines if convicted on three counts, including illegal entry into the United States, altering a passport and lying to a federal officer. She has been in custody without bail since July 19 when she was seized at the airport in McAllen, Texas, for not having a visa. An FBI affidavit said Ahmed admitted she entered the United States illegally by crossing the Rio Grande from Mexico into Texas.