Federal prosecutors examining the Ukraine business dealings of President Trump’s personal attorney Rudy Giuliani have looked at his bank records and are questioning witnesses, The Wall Street Journal reports. The probe—led by U.S. attorney’s office in the Southern District of New York—is scrutinizing Giuliani’s meetings and work for a Ukrainian mayor. In addition to looking at his bank records, investigators have questioned witnesses about Giuliani since at least August. The investigation’s scope is not clear. Giuliani told the newspaper that he was unaware of any investigation and denied doing anything wrong. “They can look at my Ukraine business all they want,” he said.

Lev Parnas and Igor Fruman, two of Giuliani's associates, were recently arrested for violating campaign finance laws. Parnas and Fruman were reportedly helping Giuliani investigate the work ex-Vice President Joe Biden’s son was doing in Ukraine. President Trump was also pushing for Ukraine to conduct a similar investigation into Bidens during a call with the Ukrainian president, which is the subject of a whistleblower complaint. Parnas and Fruman have been released on $1 million bonds, and are slated to appear in court on Thursday.