On Thursday morning, FBI agents raided the City Hall office of Chicago Alderman Ed Burke, a powerful figure in Illinois state politics and a former property tax attorney for Donald Trump.

It’s not yet clear whether the search has anything to do with Trump. Details are scant and the FBI has not said who the target of the investigation is, or what the federal agents thought they might find in Burke’s office. As of Thursday afternoon, FBI Chicago spokeswoman Janine Wheeler simply confirmed that agents were “executing search warrants at multiple locations.”

But because Burke had worked for President Trump on his Chicago real estate project, speculation immediately started flying about whether the FBI raid might be part of the bigger probe into the president.

Then again, it’s also quite possible that the raid has nothing to do with Trump at all: Burke, Chicago’s longest-serving alderman, has been the focus of federal investigations in the past.

“There have previously been several other investigations such as this, Burke said in a Thursday statement. “In every instance we cooperated fully. And in every instance nothing has been found. So once again we will be cooperating fully and I am completely confident that at the end of the day nothing will be found amiss in this instance either.”

Here’s what we know and don’t know about the raid.

What we know

Roughly 15 federal agents showed up at Burke’s office in Chicago’s City Hall around 7:30 am Central time and took over the office by kicking out staffers and papering over the windows, according to reports from the Chicago Sun-Times and Chicago Tribune.

The agents left in the early afternoon with “one cardboard file box, a computer and two computer monitors,” according to the Sun-Times.

The windows were also papered over at Burke’s office in Chicago’s 14th Ward, according to the Tribune.

Burke is not a stranger to being investigated: In his 50 years in public office, he’s survived numerous scandals, including one related to payroll in 2014.

Burke’s law firm, Klafter & Burke, began representing Donald Trump in 2006, while the Trump International Hotel and Tower in Chicago was under construction. Burke had previously voted to approve the project as an alderman.

Burke’s law firm saved Trump $14.1 million in property taxes between 2006 and 2018, according to the Sun-Times.

Burke stopped representing Trump in May 2018, citing “irreconcilable differences,” according to the Sun-Times. At the time, the newspaper suggested that Burke might be worried that his work with the president could alienate the Hispanic voters who make up the majority of his constituents.

The Thursday investigation into Burke’s offices was conducted by the US Attorney’s Office in Chicago, a spokesperson for US Attorney John Lausch told the Tribune. It was not conducted by special counsel Robert Mueller, which suggests it may be unrelated to the president’s wider probe.

The FBI did not search Burke’s law offices in Chicago.

What we don’t know