Actresses Felicity Huffman and Lori Loughlin are among dozens of people charged by the FBI in an elite college admission scheme, documents unsealed Tuesday in Boston revealed.

The Hollywood stars allegedly joined CEOs of private and public companies, real estate professionals and a fashion designer in paying up to $6 million in bribes to ensure that their children were accepted to schools such as Yale and Georgetown. Most of the parents paid $250,000 to $400,000 per student.

The alleged scheme, which the FBI called a nationwide conspiracy, allowed parents to pay for their children to cheat on exams and apply to elite schools as student athletes, regardless of their actual skills. Top college coaches at the schools are also among those charged, but authorities said they are not investigating the schools themselves.

Federal prosecutors said 33 parents bribed entrance exam administrators along with varsity coaches and administrators.

The bribery ring allegedly got its start several years ago when William Rick Singer founded a for-profit college admissions company in Newport Beach, California, that masqueraded as a not-for-profit group, according to authorities. He agreed to plead guilty to charges including racketeering and money laundering conspiracy.

Singers sham charity allowed him to conceal the nature of the payments made by parents, who could then take the tax write-off at the end of the year, U.S. Attorney Andrew Lelling said at a press conference Tuesday morning.

More than 200 law enforcement officials were involved in Operation Varsity Blues over the course of a year, arresting over 50 people in six states on both coasts, authorities said at the press conference. Most defendants had been taken into custody as of noon Eastern time on Tuesday.

The plot allegedly affected applications to a long list of schools including Yale, Stanford, the University of Texas, the University of Southern California, the University of California at Los Angeles, the University of San Diego and Wake Forest University.

Some parents allegedly paid for someone to pose as their child during entrance exams and even during classes with those scores submitted as part of the college application, according to court documents. Other cases involved exam administrators allegedly providing students with answers during the tests or correcting wrong answers afterward.

Lelling alleged that some parents also falsely claimed that their children had learning disabilities, requiring extra time on the exams, and that those claims were bolstered by notes from therapists.

Everybodys doing it seemed to be the rationale most parents accepted as they negotiated terms to cheat. The whole world is scamming the system, an unnamed cooperating witness told one parent.