Eamonn Higgins has never earned a college degree in his own name, but prosecutors allege that for the past seven years the 46-year-old has been going to school non-stop for dozens of other students. Authorities alleged that Higgins collected tens of thousands of dollars from foreign students from Saudi Arabia, the United Arab Emirates, Lebanon, Kuwait, Turkey and Qatar before he or his accomplices took their exams at 10 Southern California community colleges and universities using doctored IDs. Higgins was charged Monday with operating a ring of illegal test-takers who allegedly helped dozens of Middle Eastern nationals obtain US student visas by passing English-proficiency exams for them – and then helped them hold onto those visas by taking college courses, passing finals and writing term papers in their names. The allegations outlined in court papers reveal a potentially dangerous security breach in the US student visa system and underscore the vulnerability of a tracking process that relies on schools and testing centers to verify the identities of people taking the mandated exams. Higgins made an appearance in US District Court in Santa Ana, California, on one count of conspiracy to commit visa fraud as federal immigration agents arrested 16 of his suspected clients who remained in Southern California. Six of Higgins' alleged clients face criminal charges, while the remaining students face deportation proceedings, said Virginia Kice, a spokeswoman for ICE. Ten additional students were not arrested but will be questioned by agents in the ongoing investigation, Kice said. A federal magistrate allowed Higgins to go free on $5,000 bail. His public defender, Elizabeth Macias, declined to comment. Higgins charged as much as $1,500 per student per exam for passing grades on exams needed to obtain their student visas or to stay current on the visas, authorities said. E-mails discovered during the investigation indicated Higgins also attended classes for his clients. One e-mail exchange with a Saudi Arabian student showed him and several others were charged a total of more than $34,000 to have others take a full course load for them, according to a court affidavit. US colleges and universities began using a specialized tracking system for foreign students after the Sept. 11, 2001, terrorist attacks, but the current investigation exposed an unexpected loophole, Parker said. The scheme operated from 2002 to 2009 at seven Southern California community colleges and three California State University campuses. The investigation into Higgins began when police in Daly City in Northern California discovered seven fake driver's licenses in a lost wallet, according to court papers. Each of the fake licenses featured a photo of Higgins' nephew. A search of law enforcement databases showed the names on the IDs matched students who had entered the country on student visas and studied in Southern California.