CHICAGO (STMW) — First, federal agents dined at several of celebrity chef Tony Hu’s Chinatown restaurants.

Then they returned in October with a warrant — hoping to feast on evidence of tax fraud, according to court records.

The FBI suspected Hu’s restaurants had been dodging taxes by underreporting gross receipts. And it laid out its allegations in a 110-page court record filed last fall as it sought to raid nine of Hu’s eateries around Chicago, as well as Hu’s South Michigan Avenue condominium. The raid went down Oct. 24.

But the details only came to light this week in previously sealed records obtained by the Chicago Sun-Times.

Hu, also identified in the documents as Hu Xiaojun and sometimes referred to as the unofficial “Mayor of Chinatown,” has not been charged criminally in connection with the raid, records show. He could not be reached for comment Monday. Multiple people said Hu is in China and is not expected to return to Chicago until next month.

An FBI spokeswoman declined to comment, citing the “underlying investigation.”

Hu is an appointed member of the Commission on Chicago Landmarks who has owned several Chicago-area restaurants through his Tony Gourmet Group, including Lao Sze Chuan. The FBI targeted that chain’s locations in Chinatown, Uptown and Downers Grove in its raid, the records show. It also sought permission to search Chinatown-area restaurants Lao Beijing, Lao Shanghai, Lao You Ju, Lao Ma La, Lao Hunan and Lao Yunnan.

Before raiding the restaurants, the feds tailed Hu in his black Mercedes-Benz as he drove to Chinatown from his South Michigan Avenue condo, according to a search warrant application. FBI agents also dined at Hu’s restaurants more than a year before the raid to get a closer look at its computer systems and standard receipts, the records show.

But agents also scoured bank records and emails documenting the restaurants’ sales, the records show. And the investigators said the numbers they found often didn’t match the amounts submitted on the restaurants’ tax forms.

For example, a manager’s spreadsheet emailed to Hu indicated Lao Sze Chuan’s Downers Grove location took in as much as $1.066 million in 2009, agents said, but the restaurant only reported $656,866 on its annual tax return for that year.

The Chicago restaurants’ average monthly bank deposits in 2013 and 2014 also tended to be higher than the receipts documented on tax forms, investigators wrote. They said the average monthly deposit for Lao Sze Chuan’s Chinatown location was $230,812, but the average monthly receipt reported to the government was $214,995.

And the average monthly deposit for Lao You Ju in Chinatown was $94,330, agents wrote, but the average monthly receipt reported on its tax forms was $82,468.

Federal agents told a judge they wanted to search Hu’s restaurants for accounting records going back to 2011, as well as records of computer and Internet use.

Records show they walked away from at least one of his eateries with a computer and various banking records.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)