The Treasury Department’s Office of Inspector General said it was launching an audit of the security controls for the federal government’s payment system after Democratic senators raised red flags about the access provided to Trump aide Elon Musk’s Department of Government Efficiency team.

The audit will also review the past two years of the system’s transactions as it relates to Musk’s assertion of “alleged fraudulent payments,” according to a letter from Loren J. Sciurba, Treasury’s deputy inspector general, that was obtained by The Associated Press.