A House committee voted Thursday to subpoena the head of the Department of Veterans Affairs, Eric Shinseki, and other top department officials, stepping up scrutiny of the agency amid allegations that secret waiting lists were used to cover up long delays for doctors’ appointments.

The subpoena from the Committee on Veterans’ Affairs covers all emails and other correspondence related to the “destruction or disappearance of an alternate or interim wait list” at the department’s Phoenix medical center. It asked for all emails from April 9 to May 8 sent to or from Mr. Shinseki; Dr. Robert A. Petzel, the department’s under secretary for health; Will A. Gunn, the department’s general counsel; and five other senior officials.

In a statement on Thursday, the Department of Veterans Affairs said it would “review and respond to the subpoena,” but a department official declined to elaborate. The department also said it would conduct “face-to-face” audits of all clinics at department medical centers to “ensure a full understanding” of the policy on how patient access is managed.

The committee chairman, Representative Jeff Miller, Republican of Florida, said the subpoena was necessary because the department had been “stonewalling” requests to provide more information about claims that an off-the-books waiting list was used to hide wait times, and that the list may have been subsequently destroyed.