Republican lawmakers sent a letter to the United States Treasury to inquire about “suspicious activity reports” related to former Vice President Joe Biden’s son, Hunter Biden, and his employment with Ukrainian energy empire Burisma.

Reuters reported on the November 15 letter sent by Senate Finance Committee Chairman Chuck Grassley and Ron Johnson, chairman of the Homeland Security and Governmental Affairs Committee, to Ken Blanco, the director of the Financial Crimes Enforcement Network:

The letter, seen by Reuters on Friday, seeks “suspicious activity reports,” or documents that financial institutions file with the department’s Financial Crimes Enforcement Network when a case of money laundering or fraud is suspected. It was unclear if any such reports exist regarding Hunter Biden, the former vice president’s son. There letter gave no evidence that Hunter Biden engaged in suspicious activity that would have been covered by such reports. The agency does not comment on the reports, a spokesman said. Fincen, as the network is known, collects more than 2 million such reports each year, and they are tipsheets that make no findings on whether illegal activity has occurred.

The letter is part of an effort in Congress to defend President Donald Trump for what Republicans say is a partisan effort by Democrats to make a phone call between Trump and Ukrainian president Volodymyr Zelensky where the Bidens’ Ukrainian dealings were discussed an impeachable offense.

The lawmakers set a Dec. 5 deadline for Treasury to respond to the request.

Reuters noted in its report that Hunter Biden served on the board of directors for Burisima, which has been investigated for corruption. The younger Biden served on the board while Joe Biden was vice president of the United States.

“In the letter, the senators said Burisma was paying Hunter Biden as much as $50,000 a month and their panels were investigating ‘potentially improper actions by the Obama administration with respect to Burisma Holdings and Ukraine,’” Reuters reported.

In the final paragraph of the Reuters report, another investigation is revealed: Grassley and Johnson have asked the U.S. National Archives and Records Administration for records of a 2016 White House meeting between Obama administration officials, representatives of the Ukrainian government, and officials from the Democratic National Committee.

Follow Penny Starr on Twitter