Rep. George Santos has been criminally charged. Here's what prosecutors say he did.

A federal grand jury has indicted Rep. George Santos, R-N.Y., on 13 counts centering around three alleged schemes, according to court documents. The congressman, who was sworn into office in January, was taken into custody Wednesday morning on Long Island.

Santos is charged with five counts of wire fraud in what prosecutors allege was a fraudulent political contribution solicitation scheme. He's charged with two counts of unlawful monetary transactions for allegedly transferring donations he received for his political campaign to accounts he controlled before spending them on personal purchases, according to the indictment.

He is charged with one count of theft of public money and two more counts of wire fraud for allegedly fraudulently applying for and receiving unemployment benefits during the pandemic.

Santos is also facing two counts of making false statements to the U.S. House of Representatives in financial disclosure reports.

He pleaded not guilty on Wednesday afternoon and said he would defend himself against the allegations in a press conference afterward. "I'm going to fight the witch hunt. I'm going to take care of clearing my name and I look forward to doing that," he said."

Scheme to solicit political contributions

Prosecutors allege Santos "devised and executed a scheme to defraud supporters of his candidacy for the House and to obtain money from them" by persuading them to contribute funds to a company he created under the "false pretense" that it would be used for his political campaign.

Santos then allegedly spent thousands of dollars of the solicited funds on personal expenses, including "luxury designer clothing and credit card payments," according to prosecutors.

Prosecutors allege Santos lied to campaign funders, telling them the company he set up was a social welfare organization or a super PAC. Campaign finance laws require expenditure committees to register with the Federal Election Commission as super PACs within 10 days of receiving contributions or spending more than $1,000 in a calendar year, but Santos allegedly knew his company was not registered as such, according to prosecutors.

Santos allegedly told donors that there were "no limits" on how much contributions could be. At least one person then made contributions to his campaign that exceeded the limit set by campaign finance laws, according to the indictment.

Santos allegedly sent prospective donors one or more text messages or emails requesting donations, claiming the funds would be used for TV advertisements to support his candidacy for the House of Representatives, according to the indictment.

Santos allegedly received two $25,000 donations from funders who were under the false impression that Santos would use the funds to put his advertisements on TV, based on text messages and emails sent to the donors, but the funds were not used for ads or campaign expenditures, according to the indictment.

Prosecutors allege the funds were then transferred into bank accounts controlled by Santos before being spent "for his personal benefit, including to make cash withdrawals, personal purchases of luxury designer clothing, credit card payments, a car payment, payments on personal debts, and one or more bank transfers" to his personal associates, according to the indictment.

Unemployment benefits

Santos is also accused of fraudulently applying for and receiving COVID-19 pandemic-era unemployment benefits, receiving about $24,744 in unemployment benefits, according to the indictment.

On June 17, 2020, Santos allegedly applied to receive New York state unemployment insurance benefits, falsely claiming that he had been unemployed since March 22, 2020, according to prosecutors.

Santos then allegedly certified his eligibility for unemployment benefits on a weekly basis through April 15, 2021, falsely attesting in each instance that he was unemployed despite being a regional director at an investment firm from Feb. 3, 2020, through April 15, 2021, according to prosecutors.

Santos allegedly received a salary of about $120,000 per year from the firm, according to prosecutors.

When asked specifically about the charge outside court, he called the accusation "inaccurate."

False statements to the US House of Representatives

Santos is also accused of making false statements in two financial disclosures to the House of Representatives that he filed as a candidate.

During his first unsuccessful campaign for office in May 2020, Santos allegedly overstated one source of income while failing to disclose a salary he received from an investment firm, according to the indictment.

When he ran for office again in 2022, Santos allegedly included falsehoods in his financial disclosure forms, according to the indictment. In his 2022 disclosure, Santos lied about earning a $750,000 salary and between $1 million and $5 million in dividends from his company, the Devolder Organization, and Santos falsely claimed to have a checking account that held between $100,000 and $250,000, and a savings account with deposits of between $1 and $5 million, according to the indictment.

ABC News' Aaron Katersky contributed to this report.