House Oversight Committee Chairman James Comer (R-Ky.) pressed Federal Reserve Chairman Jerome Powell for information as his panel probes the collapse of Silicon Valley Bank (SVB), alleging the agency has been insufficiently responsive to previous requests.

In a Monday letter to Powell, Comer and Rep. Lisa McClain (R-Mich.), chair of the subcommittee on Health Care and Financial Services, said the committee had received some publicly available and nonpublic confidential supervisory information they requested from the Federal Reserve Bank of San Francisco in late April.

But Comer and McClain said they had not received adequate responses to requests for examination and audit reports, meeting minutes, communications and other information.

The committee is investigating the role the San Francisco Fed, which was tasked with supervising SVB, and other state and federal regulators played in the bank’s April 27 failure.

Regulators raised concerns about risks within SVB and Signature Bank, which collapsed after customers withdrew billions following the failure of Silicon Valley Bank, but a Government Accountability Office report found they did not take steps to address serious mismanagement at the banks.

Former SVB CEO Gregory Becker was a member of the San Francisco Fed board, raising additional questions about regulatory oversight ahead of the collapse.

The San Francisco Fed responded to the initial request with publicly available documents, Comer and McClain wrote, including an overview of the Federal Reserve System and a copy of the Board’s postmortem review of the Fed’s supervision of SVB.

San Francisco Fed officials later informed committee staffers “the Fed Board was asserting privilege over a majority of the requested materials.”

“We have received the letter and plan to respond,” a Fed spokesperson said in an email.

The San Francisco Fed did not immediately return a request for comment.

Committee staffers discussed concerns about the assertion with the Fed board staff on June 1 and secured an agreement to receive nonpublic materials and other documents, according to the letter.

Comer and McClain said they had received some nonpublic confidential supervisory materials but that they “have not received any communications responsive to our requests.”

They requested additional information that could provide new insights into the failure to respond to the initial request.

“We look forward to continuing working with you and your staff so that the Committee can receive a fully responsive production,” Comer and McClain wrote.