On Friday, prolific political fundraiser Jeff Thompson's office was raided in northwest D.C.
The raid was part of an ongoing investigation into Mayor Vince Gray's 2010 campaign for mayor.
Thompson has helped raise money for numerous political candidates over the years, and played a significant role in Gray's successful mayoral run two years ago.
A source told News4's Tom Sherwood that Friday's "raid on Thompson was a significant step up in the U.S. Attorney's investigation."
Former mayoral candidate and short-time city auditor Sulaimon Brown made allegations last year that Vince Gray gave him money to focus criticism on incumbent Mayor Adrian Fenty during the campaign. Brown also said he was offered a District job in exchange for the stalking-horse attacks.
No criminal charges have been filed against Thompson, but the U.S. Attorney's Office released a statement to the Post and the City Paper confirming law enforcement activity at his offices on 15th Street Northwest.
The firm run by Thompson hold's the District's health service contract, estimated to be worth $300 million per year. In addition, he has an accounting firm.