A Senate panel is still waiting for answers from a top federal auditor more than four months after its top members requested documents and other information as part of an investigation into alleged misconduct and abuse of power by the official.

Sens. Claire McCaskill (D-Mo.) and Ron Johnson (R-Wis.), who head  the Senate Subcommittee on Financial and Contracting Oversight, issued a letter to Homeland Security Deputy Inspector General Charles Edwards on Wednesday asking him to fully comply with demands they made in late-June.

The panel is examining nine claims against Edwards, including allegations of nepotism, withholding information about the Secret Service’s Colombian prostitute scandal, misuse of agency funds and requiring subordinates to do his homework for PhD courses.

The letter said Edwards has provided only partial responses to 16 document requests and no response at all to five of them. It also said six senior special agents have declined to be interviewed.

“We understand that your office has failed to conduct electronic searches for many of the documents and communication identified by the subcommittee,” the letter said. “In order to ensure that federal laws have not been broken, and that the integrity of the Office of Inspector General has not been compromised, it is imperative that we have access to the information requested.”

The lawmakers did not set a deadline for providing the documents or threaten to subpoena Edwards.

The government watchdog group Cause of Action, which has requested some of the same information from the Department of Homeland Security, said the delay in providing information represents an “alarming stance in their affront to transparency.”

“IG Edwards must be held accountable for his alleged misconduct and his deliberate and continued objection to the public’s right to know about it,” Cause of Action director Dan Epstein said in a statement Thursday.

The inspector general’s office declined to comment on the matter Friday.

In a July statement to The Post, Edwards said: “I am very disturbed that false allegations have been made against me, but more importantly, I am very concerned that this matter may negatively impact the important oversight work of the Office of Inspector General … I will defend myself against these personal attacks.”

Edwards’ office is investigating U.S. Citizenship and Immigration Services Director Alejandros Mayorkas, whom President Obama has nominated to become second-in-command at the Department of Homeland Security.

The Mayorkas probe centers around whether the immigration official helped secure visas for foreign workers on behalf of a firm with ties to Virginia gubernatorial candidate Terry McAuliffe (D) and Anthony Rodham, brother of former secretary of state Hillary Clinton.

Mayorkas has denied the allegations of improper influence, saying during a congressional hearing this year that he met with McAuliffe, but only to discuss the pace of visa approvals.

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