(NEW YORK) — On the night he was elected the 110th mayor of New York City, former police Capt. Eric Adams vowed to fight for those “this city has betrayed.”

“This city betrayed New Yorkers every day, especially the ones who rely on it the most. My fellow New Yorkers, that betrayal stops on January 1,” Adams said that night in November 2021.

For the past year, federal authorities have been investigating the possibility of corruption at City Hall, issuing subpoenas for Adams and members of his inner circle.

On Thursday, New York Police Commissioner Edward Caban resigned a week after sources told ABC News the FBI seized his cell phone as part of the federal investigation.

Caban released a statement saying he was stepping down because the “noise around recent developments” had made his primary focus on the NYPD “impossible and has hindered the important work our city requires.” He said he will “continue to fully cooperate with the ongoing investigation.”

Caban’s family has connections to nightlife. Richard Caban, the brother of Edward Caban and a former NYPD lieutenant, owned a now-shuttered Bronx restaurant, Con Sofrito. Edward Caban’s twin brother, James Caban, a former NYPD sergeant, owned a Bronx apartment building that once had a bar on the first floor named Twins.

Meanwhile, Adams has denied any wrongdoing. The mayor has not been charged with any crimes stemming from the investigations.

Federal authorities have not commented on what they are specifically investigating. Sources have told ABC News that one of the probes concerns city contracts and a second involves the enforcement of regulations governing bars and clubs.

“I say over and over again, as a former member of law enforcement, I’m very clear. We follow the rules. We make sure that we cooperate and turn over any information that is needed and it just really would be inappropriate to get in the way of the review while it’s taking place,” Adams said in an interview with CBS New York on Sept. 5.

None of the mayor’s aides who have been subpoenaed, had their homes searched, or their electronic devices seized by investigators have been charged with any crimes.

Here is a timeline of the subpoenas, searches and seizures dogging Adams and his inner circle:

Nov. 2, 2023 – FBI agents search the Crown Heights, Brooklyn, home of Brianna Suggs, a campaign consultant and top fundraiser for Adams. Federal agents also search the New Jersey home of Rana Abbasova, the mayor’s international affairs aid. That same day, Adams unexpectedly returned to New York from Washington, D.C., to “address the matter,” despite planned meetings with White House officials and other big city mayors on immigration. The investigation involves a construction company, KSK Construction Group, based in Williamsburg, Brooklyn, sources told ABC News. KSK donated about $14,000 to Adams’ 2021 campaign. Suggs has not been charged with any crimes connected to the probe.

Nov. 6, 2023 – The FBI seizes Mayor Adams’ electronic devices, including an iPad and a cell phone, as part of a federal probe. Sources told ABC News that the investigation was seeking to determine whether the mayor’s campaign received illegal foreign donations from Turkey with a Brooklyn construction company as a conduit.

Nov. 15, 2023 – Adams launches a legal defense fund intended to defray expenses in connection with inquiries by the U.S. Attorney’s Office for the Southern District of New York into his mayoral 2021 campaign committee.

Jan. 15, 2024 – Vito Pitta, Adam’s longtime campaign compliance lawyer, releases a statement saying the mayor’s legal defense fund had raised $650,000 in just two months.

Feb. 29, 2024 – The FBI, investigating Adam’s fundraising, searches the Bronx home of Winnie Greco, the director of Asian affairs for Adam’s administration. The probe also involves a construction company, KSK Construction Group, sources tell ABC News.

April 5, 2024 – ABC News reports that the FBI is investigating whether Adams received free upgrades on Turkish Airlines, Turkey’s national carrier.

July 2024 – Federal prosecutors in New York serve Adams grand jury subpoenas as part of what sources tell ABC News is an ongoing corruption investigation involving whether his campaign sought illegal donations from Turkey in exchange for pressuring the fire department to rush an inspection of the new Turkish consulate in New York City. The subpoenas seek communications and documents from the mayor, according to sources. In an interview with ABC New York station WABC, Adams says, “Like previous administrations that have gone through subpoenas, you participate and cooperate. You see a subpoena, and you respond. At the end of the day, it will show there is no criminality here.”

Sept. 4, 2024 – The FBI conducts searches at the homes of two of Adams’ closest aids. Federal agents search the upper Manhattan home of First Deputy Mayor Sheena Wright, who is engaged to Schools Chancellor David Banks. Agents also search the Hollis, Queens, home of Deputy Mayor for Public Safety Phil Banks. The FBI seized evidence, including electronics, as part of the searches, sources told ABC News. David and Phil Banks are brothers and both have known Adams for years.

Sept. 5, 2024 – ABC News reports that federal investigators subpoenaed the cell phones of four high-ranking New York Police Department officials, including NYPD Commissioner Caban. The subpoenas are part of the same investigation that sent the FBI to search the homes of Deputy Mayors Wright and Banks, sources told ABC News. Tim Pearson, a close adviser to Adams, also receives a subpoena for his cell phone, sources said. The subpoenas, according to sources, are connected to an undisclosed investigation separate from one into whether Adams allegedly accepted illegal donations from Turkey in exchange for official favors.

Sept. 10, 2024 – Adams declines to say at a news conference if he remains confident in Police Commissioner Caban amid news reports claiming Caban is under pressure to resign. When asked if he was confident in Caban’s leadership, Adams says, “I have the utmost confidence in the New York City Police Department.”

Sept. 12, 2024 — Commissioner Caban resigns. His attorneys, Russell Capone and Rebekah Donaleski, release a statement saying they have been informed that Caban is “not a target of any investigation being conducted by the Southern District of New York” and that he “expects to cooperate fully with the government.” Caban says in a statement, “My complete focus must be on the NYPD — the Department I profoundly honor and have dedicated my career to serving. However, the noise around recent developments has made that impossible and has hindered the important work our city requires. I have therefore decided it is in the best interest of the Department that I resign as Commissioner.”

Adams confirms he accepts Caban’s resignation and announces he has appointed former FBI agent and former New York Homeland Security Director Tom Donlon as interim commissioner. “I respect his decision and I wish him well,” the mayor says of Caban. “Commissioner Caban dedicated his life to making our city safe, and we saw a drop in crime for the 13 of the 14 months that he served as commissioner.”

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