The special counsel and congressional committees investigating Russian interference in the 2016 election are looking into possible money laundering by President Donald Trump’s former campaign chair Paul Manafort, the Wall Street Journal reported late Thursday.

The Wall Street Journal reported, citing a single unnamed source familiar with the matter, that special counsel Robert Mueller, who is overseeing the federal probe into Russian meddling, began an inquiry several weeks ago into possible money laundering by Manafort.

The Senate and House intelligence committees are also looking into the matter, unnamed sources with knowledge of the congressional probes told the Wall Street Journal.

According to the report, those sources also said the Senate Intelligence Committee is looking into whether any of President Donald Trump’s businesses have financial ties to Russian interests. The panel has received reports from the Financial Crimes Enforcement Network, a bureau of the Treasury Department, per the Wall Street Journal.

Spokespeople for Manafort and Mueller declined to comment to the Wall Street Journal.

The New York Times reported Wednesday, citing financial records filed in Cyprus in 2016, that Manafort owed as much as $17 million to pro-Russia interests before he joined Trump’s campaign, where he requested no salary in his capacity as chairman.

NBC News reported in March that Manafort closed several accounts with a bank in Cyprus after it launched an internal investigation into potential money laundering.