The special counsel overseeing the Justice Department’s investigation into Russia’s meddling in last year’s U.S. presidential election is examining transactions involving Trump’s businesses and those of his associates, according to Bloomberg.

A person familiar with the investigation told the news outlet that Robert Mueller is “looking at Russian purchases of apartments in Trump buildings, Trump’s involvement in a controversial SoHo development with Russian associates, the 2013 Miss Universe pageant in Moscow and Trump’s sale of a Florida mansion to a Russian oligarch in 2008.”

Later Thursday, the Wall Street Journal reported that Mueller is also investigating potential money laundering by Paul Manafort, who served as Trump’s campaign manager part of last year. Manafort, who has been scrutinized for work he did for a pro-Russia political party in Ukraine, has been called to testify before the Senate Judiciary Committee next week, along with the president’s eldest son, Donald Trump Jr.

The Bloomberg report follows a bombshell New York Times interview with Trump published Wednesday in which the president said Mueller would cross a line if he looked into the Trump family’s finances beyond Russia.

“I think that’s a violation. Look, this is about Russia,” Trump told the Times.

The president further seemed to imply he was not ruling out possibly firing Mueller.

Last month, after a close friend of Trump said the president was considering firing Mueller, White House Deputy Press Secretary Sarah Huckabee Sanders said he had “no intention” of doing so.

Neal Katyal, a former Justice Department official who almost 20 years ago spent 18 months working on the federal regulations that allowed for Mueller’s appointment, wrote last month that the president theoretically has the power to fire him. However, Katyal added, doing so could lead to impeachment proceedings in Congress.

Sen. Richard Blumenthal (D-Conn.) on Thursday said Trump’s warning to Mueller in the New York Times “raises the specter of obstruction of justice.”

This article has been updated with the Wall Street Journal report on Manafort coming under the scope of Mueller’s probe.