Both the FBI and the Securities and Exchange Commission are looking into Sen. Bob Corker’s (R-TN) personal finances, the Wall Street Journal reported Tuesday.

The scrutiny reportedly stems from Corker’s stock transactions with CBL & Associates Properties Inc., a leading developer of shopping centers and malls, from which he earned millions of dollars. Anonymous officials familiar with the investigation told the newspaper the probe is focused on alleged accounting fraud at CBL; they said they they’ve found no evidence Corker committed any wrongdoing.

As the newspaper reported last fall, Corker failed to report millions in assets and income on his annual financial disclosure forms since coming to the Senate in 2007. He revised several years’ worth of disclosure reports after the WSJ inquired about the inconsistencies in his finances.

The senator’s spokeswoman, Micah Johnson, blamed a complaint filed with the SEC by advocacy group Campaign for Accountability for the feds looking into Corker’s finances.

“A politically motivated special interest group that refuses to disclose its donors continues to make baseless charges against Senator Corker, and we know that any effort to examine his actions will result in their smear campaign being discredited,” Johnson said in a statement provided to Politico.

Politico reported that Corker worked for a CBL contractor after college and has accepted campaign donations from senior executives at the company, to whom he has close ties.

Corker serves as the chairman of the Senate Foreign Relations Committee and a senior member of the Senate Banking Committee. He is rumored to be the short list for Donald Trump’s vice presidential pick, and met with the presumptive GOP nominee for an extended conversation on Monday.