It’s one of several federal corruption investigations that have ensnared Mr. Adams’s administration. Here are some key events that led up to the indictment of the mayor:

Nov. 2, 2023: The F.B.I. raids the home of the chief fund-raiser to Mayor Eric Adams.

Federal agents raided the Brooklyn home of Brianna Suggs, a recent college graduate who had been in charge of Mr. Adams’s fund-raising operation when he ran for mayor in 2021. Mr. Suggs was 23 years old when the mayor picked her for the job, and many Democratic officials who worked in fund-raising were shocked that he had chosen someone for the role with so little professional experience.

The agents seized three iPhones and two laptop computers from Ms. Suggs’s home; they also took papers and other evidence, including something agents identified as a “manila folder labeled Eric Adams,” as well as seven “contribution card binders” and other materials, according to the search warrant documents.

Nov. 2, 2023: The F.B.I. raids the homes of an aide in the mayor’s international affairs office and a former Turkish Airlines executive who served on his transition team.

Investigators also searched the New Jersey homes of Rana Abbasova, an aide in Mr. Adams’s international affairs office, and Cenk Öcal, a former Turkish Airlines executive who served on his transition team, according to people familiar with the matter.

Ms. Abbasova was the mayor’s longtime liaison to the Turkish community when Mr. Adams was Brooklyn borough president. Mr. Öcal was the general manager of the New York office of Turkish Airlines until early 2022.

Nov. 6, 2023: The F.B.I. seizes the mayor’s phones and iPad.

In early November, F.B.I. agents approached Mr. Adams and his security detail after he had attended an event in Manhattan. The agents asked the security team to step aside before climbing into the mayor’s S.U.V. with him and taking his devices, pursuant to a court-authorized warrant. The devices were returned to the mayor within a matter of days, according to two people familiar with the situation. Law enforcement investigators can make copies of data on seized devices.

A lawyer for the mayor, Boyd Johnson, said at the time that Mr. Adams had not been accused of wrongdoing and had “immediately complied with the F.B.I.’s request and provided them with electronic devices.”

Mr. Johnson also said that Mr. Adams had already “proactively reported” at least one instance of improper behavior.

Nov. 28, 2023: Adams announces that his chief fund-raiser is out.

Weeks after agents searched Ms. Suggs’s home, Mayor Adams said during a weekly press briefing that she was no longer managing his political fund-raising. He declined to say why he had removed her from the position. Ms. Abbasova was also placed on leave after City Hall learned she had “acted improperly,” according to a spokesman for the mayor.

Feb. 5, 2024: A retired police inspector pleads guilty to funneling illegal funds to the mayor’s campaign.

Dwayne Montgomery, a former police inspector, pleaded guilty to misdemeanor conspiracy, admitting to directing straw donors — people who make campaign contributions using someone else’s money — to contribute to the mayor’s campaign. Mr. Montgomery was indicted in July 2023, along with five others, including four construction executives and a bookkeeper. Mr. Montgomery agreed in his plea not to organize or host any fund-raisers or to solicit contributions for a campaign, for one year.

The mayor was not implicated in the indictment nor accused of any wrongdoing.

Feb. 29, 2024: The F.B.I. searches the homes of the mayor’s Asian affairs adviser, who was a prominent fund-raiser for his campaign.

Agents searched two houses that belonged to Winnie Greco, an aide who was a prominent fund-raiser and who had close ties to the Chinese community in New York City. She became the mayor’s director of Asian affairs when he took office in 2022. The searches were part of an investigation conducted by prosecutors from the U.S. attorney’s office in Brooklyn and it was unclear what the investigation was focused on and whether it was related to the mayor.

Agents also executed a search warrant at the New World Mall in Flushing, Queens, where Mr. Adams had made regular appearances, including to deliver remarks at a Lunar New Year gala.

July 2024: Federal prosecutors serve a new round of subpoenas to the mayor, his election committee and City Hall.

The subpoenas sought information in a number of areas, including travel by the mayor, his aides and others, and fund-raising. It was unclear what prompted the new subpoenas.

Sept. 4, 2024: Federal agents seize the phones of the police commissioner, the first deputy mayor, the schools chancellor and others.

Top city officials who had their phones seized included the police commissioner, Edward A. Caban; the first deputy mayor, Sheena Wright; her partner, David C. Banks, the schools chancellor; the deputy mayor for public safety, Philip Banks III; and a senior adviser to the mayor, Timothy Pearson.

The seizures appeared to be separate from the corruption investigation focused on the mayor and his campaign fund-raising, but the actions further destabilized his administration.

Terence Banks, a consultant who is the brother of both the schools chancellor and the deputy mayor of public safety, had his home searched and his phone seized. Agents seized the phones of his brothers because they believed they might find evidence of bribery and other crimes, including fraud and violations of the Travel Act, according to people with knowledge of the matter.

Sept. 12, 2024: The police commissioner resigns.

Mr. Caban, the New York police commissioner, resigned at the request of City Hall, which asked him to step aside after federal investigators seized his phone. Media coverage about the investigations had “created a distraction for the department,” Mr. Caban said in an email to members of the Police Department.

Lawyers for Mr. Caban said in a statement that federal prosecutors had told them that he was not a target of the investigation and that he intended to fully cooperate with the government.

Sept. 15, 2024: The mayor’s chief counsel resigns.

Lisa Zornberg resigned from her post as the mayor’s counsel and chief legal adviser. She had been one of the mayor’s fiercest defenders, encouraging New Yorkers not to rush to judgment. She formerly worked as a senior Manhattan federal prosecutor in the office that is currently conducting three separate corruption investigations into the mayor and some of his senior aides.

Sept. 16, 2024: Two former Fire Department chiefs are arrested on bribery charges.

Brian E. Cordasco, 49, and Anthony M. Saccavino, 59, ran the Department’s Bureau of Fire Prevention until earlier this year. They were arrested and accused of accepting tens of thousands of dollars in bribes to speed up the fire-safety approval process for building projects across the city.

There was no indication that the case is related to any of the federal corruption investigations swirling around the mayor, his campaign and some of his most senior aides.

Sept. 21, 2024: Federal agents search the home of the interim police commissioner.

Thomas G. Donlon, who took the interim role after Mr. Caban resigned, said federal agents searched his home and seized materials that were unrelated to the Police Department. According to two federal officials with knowledge of the matter, the materials were classified documents that had been in Mr. Donlon’s possession for years.

Sept. 23, 2024: The city’s health commissioner says he will resign.

Dr. Ashwin Vasan, who led New York City out of the coronavirus pandemic, became the third top administration official to resign in September amid the investigations. His decision will go into effect early next year. Dr. Vasan said he decided to step down because he wanted to spend more time with his family. A City Hall spokesman said the departure was unrelated to the federal inquiries, and the commissioner affirmed that in a brief interview with The Times.

Sept. 23, 2024: It is reported for the first time that federal prosecutors are looking into the mayor’s dealings with five countries besides Turkey.

The other countries are Israel, China, Qatar, South Korea and Uzbekistan and the demand for information was made in expansive grand jury subpoenas issued in July to City Hall, the mayor and his campaign. This information had not been previously reported.

Sept. 24, 2024: The schools chancellor says he will resign.

David C. Banks, the chancellor of the New York City public schools system, said that he would resign from his role at the end of December. The announcement came weeks after federal agents seized his phone.

Sept. 25, 2024: Representative Alexandria Ocasio-Cortez becomes the most prominent elected official to call for Adams’s resignation.

Ms. Ocasio-Cortez, who represents parts of Queens and the Bronx, said in a statement to The New York Times that she could “not see how Mayor Adams can continue governing New York City.”

“The flood of resignations and vacancies are threatening government function,” she said. “Nonstop investigations will make it impossible to recruit and retain a qualified administration.”

“For the good of the city,” she added, “he should resign.”

The call from Ms. Ocasio-Cortez, a national leader of the Democratic Party’s progressive wing, came after a handful of other New York lawmakers urged Mr. Adams to step down.

Sept. 25, 2024: News of Mayor Eric Adams’s indictment is made public.

Eric Adams will be the first sitting New York City mayor to face criminal charges.