Singer is scheduled to plead guilty on Tuesday in Boston federal court to charges, including racketeering, money laundering and obstruction of justice, according to court papers.
Huffman was arrested at her home by armed Federal Bureau of Investigation agents and was later released on bail after her husband, Shameless actor William H.
Huffman later appeared in court, and was set free after posting $250,000 bail.
Loughlin was out of town at the time due to filming but has since turned herself in to authorities.
The largest college admissions fraud scam unearthed in United States history was run out of a small college preparation company in Newport Beach, California, that relied on bribes, phoney test takers and even doctored photos depicting non-athletic applicants as elite competitors to land college slots for the offspring of rich parents, prosecutors said. Fifty people, including Macy's wife, actress Felicity Huffman and actress Lori Loughlin, were charged Tuesday in a scheme in which wealthy parents allegedly bribed college coaches and other insiders to get their children into some of the nation's most elite schools.
The FBI says actress Lori Loughlin has been taken into custody in connection with a scheme in which wealthy parents paid bribes to get their children into top colleges.
Meanwhile, celebrities have jumped on social media to comment on the nationwide college admissions scam and the alleged involvement of two of their own, Huffman and Loughlin.
Loughlin is accused of paying Singer $500,000 to help cheat her daughters' way into the University of Southern California by bribing rowing coaches at the school to pretend the girls were gifted rowers.
Three cooperating witnesses helped the federal authorities build their case against Singer and the participants in the scheme, which reportedly included recordings of Huffman and emails from Loughlin.
The U.S. Attorney's Office for the District of MA told E!
"Full House", what's going to happen to Fuller House'?
A Hallmark Channel spokeswoman said the network hasn't decided what effect, if any, her arrest will have on programming.
Several defendants, including Huffman, were charged with conspiracy to commit fraud, punishable by up to 20 years in prison.
Athletic coaches from Yale, Stanford, USC, Wake Forest and Georgetown, among others, are implicated, as well as parents and exam administrators.
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