Eamonn Daniel Higgins spent seven years in college. Between 2002 and 2009, he attended 10 different schools in Southern California, including Cal State L.A., Irvine Valley College and Santa Monica College, according to federal prosecutors. During that time, he studied sociology, marketing, English, business and math.

But Higgins was not a student and wasn't registered in any of the classes, authorities said. Rather, dozens of foreign students -- all from the Middle East -- were paying him to sit in class, take exams and write papers so that their student visas would remain valid, according to a charging document filed in the case. Students paid up to $1,500 for course assignments and finals and about $1,000 for English and writing proficiency exams, prosecutors allege.

U.S. Immigration and Customs Enforcement agents said the demand for Higgins' services was so great that he hired staff, including a blond woman who they believe posed as an Middle Eastern man.

Higgins, 46, a U.S. citizen who lives in Laguna Niguel, surrendered to authorities Monday and pleaded not guilty in U.S. District Court in Santa Ana to conspiracy to commit visa fraud. He is free on $5,000 bail. If convicted, he faces up to five years in federal prison.

Higgins and his attorney, federal public defender Elizabeth Macias, declined to comment after the hearing.

Authorities believe Higgins earned hundreds of thousands of dollars helping about 120 people from Saudi Arabia, Lebanon, Kuwait, Turkey and Qatar maintain their student visa status.