New York City Mayor Eric Adams speaks during a press conference at the City Hall, after it was revealed that he received a fresh round of federal grand jury subpoenas, New York City, U.S., August 16, 2024.

Adam Gray | Reuters

New York City Mayor Eric Adams has been indicted on criminal charges in federal court in Manhattan, a source familiar with the matter told CNBC on Wednesday night.

The indictment, which remains sealed for now, at least in part accuses Adams of criminal conduct related to contributions to his 2021 mayoral campaign, and at least one count involves a contribution by a foreign national.

A source said that the indictment mentions up to $20 million in donations that Adams’ campaign received as a result of matching fund program that the city’s Campaign Finance Program offers candidates for small-dollar donations made to them by residents of New York City. That program gives candidates up to eight times the amount of a small-dollar donation from an individual.

Adams, a 64-year-old former police captain, is at least the second New York mayor to be criminally charged while still in office.

And he is the first official in his administration to be charged as a result of multiple pending investigations that have ensnared the New York Police Department and the city’s top schools’ official.

It was previously known the Manhattan U.S. Attorney’s Office was investigating Adams for potentially conspiring with the government of Turkey to funnel illegal donations into that campaign.

The New York Times on Monday reported that prosecutors had submitted grand jury subpoenas to City Hall, Adams, and his campaign in July demanding information related to five other countries: Israel, China, Qatar, South Korea, and Uzbekistan.

Adams gave a defiant statement Wednesday night after news of the indictment broke.

“It is now my belief that the federal government intends to charge me with crimes,” Adams said in a video statement. If so, these charges would be entirely false, based on lies.”

“But they would not be surprising. I always knew that If I stood my ground for all of you that I would be a target — and a target I became.

“If I am charged, I am innocent and I will fight this with every ounce of my strength and spirit,” said Adams, who after working in the Police Department served as a state senator and Brooklyn Borough president.

The U.S. Attorney’s Office and the FBI declined to comment on the indictment.

Earlier Wednesday, Rep. Alexandria Ocasio-Cortez, D-N.Y., called on the mayor to resign, saying the “flood of resignations and vacancies” resulting from various federal probes of administration officials “are threatening government functions.”

“For the good of the city he should resign,” Ocasio-Cortez said.

After news of the indictment broke, a growing number of elected officials and other political figures in New York called on Adams to step down, among them city Comptroller Brad Lander and state Sen. Zellnor Myrie, who are both running for mayor next year, and former comptroller Scott Stringer, who is weighing a run for City Hall.

If Adams resigns before his first term in office ends, he would be replaced by New York City Public Advocate Jumaane Williams as acting mayor.

Democratic NYC Mayoral candidate Eric Adams raises hands with Jumaane Williams, New York City Public Advocate, and NYC Comptroller candidate Brad Lander during a Get Out the Vote (GOTV) rallyin front of Brooklyn Borough Hall on October 22, 2021 in Downtown Brooklyn in New York City.

Michael M. Santiago | Getty Images

There are multiple federal investigations into Adams and people affiliated with him and his administration.

On Tuesday, city Schools Chancellor David Banks told Adams he expected to retire at the end of 2024.

Banks’ surprise announcement came weeks after federal authorities seized electronic devices belonging to him, his brother, Deputy Mayor Phil Banks, and his fiancee, Deputy Mayor Sheena Wright.

Another Banks brother, Terence, is being investigated by the Manhattan U.S. Attorney’s Office in connection with the allocation of city contacts worth millions of dollars to the companies who received them after hiring Terence Banks’ consulting firm.

Read more CNBC politics coverage

The same federal prosecutors’ office is investigating whether James Caban, the twin brother of former New York Police Commissioner Edward Caban, exploited his ties to his brother and the NYPD to benefit his nightclub security business.

Edward Caban resigned as police commissioner on Sept. 12, a week after his own phone was seized by federal investigators.

Three days after Edward Caban resigned, Adam’s mayoral counsel and chief legal advisor Lisa Zornberg resigned, saying she had “concluded that I can no longer serve in my position.”

Last Friday, federal investigators executed search warrants at the homes of Thomas Donlon, the acting NYPD commissioner.

Donlon, who is a former top FBI counterterrorism official in New York, said this week that the investigators “took materials that came into my possession approximately 20 years ago and are unrelated to my work with the New York City Police Department.”

This is breaking news. Please refresh for updates.