Wells Fargo, the second largest US bank by market value, this month paid USD 185 million in fines as it admitted that employees had boosted sales figures by opening some two million deposit and credit accounts in customers' names without their knowledge.
Bank staff did so, regulators said, to generate millions of dollars in improper fees from the accounts and earn performance bonuses for themselves.
The bank said last week it had fired 5,300 employees connected to the problem, but questions remain over whether bank executives may have escaped unpunished.
"In addition, the committee is requesting that Wells Fargo and regulators provide internal documents relating to the discovery and timing of these practices, and is asking company officials to appear for transcribed interviews," the committee said in a statement.
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Others called for transcribed interviews will include the bank's chief financial officer, chief operating office and chief risk officer, the committee said.
The Wall Street Journal reported on Wednesday that federal prosecutors had also opened a probe.
The policy activist organization Public Citizen on Friday also announced it had lodged a shareholder resolution calling on Wells Fargo to explore the possibility of breaking itself up.
"Taking CEO Stumpf at his word, then, we believe he effectively argues that his firm is so large as to be unmanageable."
Bartlett Naylor, the Public Citizen advisor who filed the resolution, told AFP he had submitted similar proposals since 2014 to JPMorgan Chase, Citigroup and Bank of America, all without success.