In a 13-count federal indictment, Republican Congressman George Santos was accused of fraud, money laundering, and theft of public monies.
As word of the charges spread, the New York representative surrendered to authorities on Wednesday.
Mr. Santos, 34, has been dogged by scandal since taking office in January, and much of his biography was shown to be false.
He could face up to 20 years in jail if convicted of the main counts.
The charges were “new to me,” the first-term lawmaker told the Associated Press earlier Wednesday.
According to the 20-page indictment, the Republican was involved in three sophisticated fraud operations.
First, federal authorities allege that he misled those who contributed to his House of Representatives campaign, instead using the funds for personal expenses such as fancy designer apparel and credit card payments.
Second, Mr. Santos is accused of participating in an unemployment insurance fraud scheme, receiving Covid-19 government help despite earning $120,000 (£95,000) through his position with a Florida-based investment firm.
Finally, prosecutors allege that the Republican lied to Congress about his financial situation.
He is charged with seven charges of wire fraud, three counts of money laundering, one case of theft of public funds, and two counts of making substantially false statements to the House.
Mr. Santos is scheduled to be arraigned on Wednesday at 13:00 local time (17:00 GMT) at a federal courthouse on Long Island. He’s had his fingerprints taken and a mugshot taken.