The Trump Inaugural Committee raised a record $107 million, and questions have been floating for two years over whether that involved illegal donations from foreigners, sweetheart deals for contractors and possible kickbacks.
It discloses that prosecutors are investigating a litany of potential crimes: conspiracy against the U.S., false statements, mail fraud, wire fraud, money laundering, inaugural committee disclosure violations, and violations of laws prohibiting contributions by foreign nations and contributions in the name of another person, also known as straw donors.
Inaugural committee spokeswoman Kristin Celauro told The Associated Press that the committee had received the subpoena and was still reviewing it.
The U.S. Attorney's Office in Manhattan declined to comment. Former Trump campaign aide Rick Gates admitted during the trial of former campaign manager Paul Manafort that he may have stolen money from the committee.
"It is our intention to cooperate with the inquiry", she said.
Later, Sanders told reporters the investigation "has nothing to do with the White House".
The chairman of the committee was Thomas Barrack, a NY real estate developer who knows Trump and has worked closely with Manafort.
The subpoena also requested documents relating to donations 'made by or on behalf of foreign nationals, including but not limited to any communications regarding or relating to the possibility of donations by foreign nationals, ' the Journal reported.
It focuses in part on one donor, venture capitalist Imaad Zuberi, and his Los Angeles company Avenue Ventures, which donated $900,000 to the inauguration, according to the Post.
According to ABC News, prosecutors are also requesting information about who attended inaugural events as Mr Trump was sworn into office in January 2017 and whether they were promised photo-ops with the president-elect, ABC News reports. The fundraising figure was more than twice as much as that for former Presidents Barack Obama and George W. Bush.