A second former State Department official is refusing to talk to Congress about what he might know about Hillary Clinton’s private email system.

Politico reports that John Bentel, who retired from the State Department in Dec. 2012, has told the House Select Committee on Benghazi and the Senate Judiciary and Homeland Security Committees that he will not meet to discuss the server and what, if anything, he knows about it.

In response to a Dec. 5 letter from Judiciary Committee chairman Sen. Chuck Grassley and Homeland Security chairman Sen. [crscore]Ron Johnson[/crscore], Bentel said he had “no memory of knowledge” about the server.

But the Senators believe Bentel may know something. As director of information resources management at the office of executive secretariat, Bentel oversaw information technology for top level officials at the State Department, including Clinton.

“It appears that you were an integral figure in the operations of the Executive Secretariat and that you would have particular and unique knowledge relevant to the committees’ inquiry,” reads the letter, which Politico obtained.

Grassley and Johnson reportedly wrote that their investigators have been told that Bentel’s subordinates knew about the server, suggesting that Bentel did as well.

“Indeed, Department personal have noted that your subordinates in the Executive Secretariat’s office, who reported directly to you, had knowledge of Secretary Clinton’s private email server, which leads one to conclude that you were likely made aware of the server,” they wrote.

Bentel may also have knowledge about Clinton’s Blackberry, Grassley and Johnson wrote.

The former secretary of state mainly used the device to send and receive work-related emails, which were routed through an email server she kept at her home. She was provided a government-issued Blackberry.

There is also some indication that Bentel’s boss at the office of the executive secretariat, Stephen Mull, knew about Clinton’s server.

The Daily Caller obtained an Aug. 30, 2011 email in which Mull told two Clinton aides and State Department under secretary for management Patrick Kennedy that Clinton’s server was on the fritz.

In that same email, Mull offered to provide Clinton with a State Department Blackberry. He wrote that Clinton’s email address would “mask her identity.” Mull also noted that Clinton’s emails would “also be subject to [Freedom of Information Act] requests.”

Besides investigating security issues related to Clinton’s use of a private server, the Senate committees are also looking into whether Clinton used the system in order to avoid complying with FOIA.

Bentel’s refusal to cooperate marks the second time a former State Department official has refused to talk to Congress about Clinton’s server.

[dcquiz] Bryan Pagliano, who directly managed the email system, also refused to talk to Congress last year. In September, he invoked his Fifth Amendment right against self-incrimination during testimony in front of the Benghazi Committee. He has since started cooperating with the FBI in exchange for immunity in order to freely discuss Clinton’s server. (RELATED: Clinton Email Server Technician Described As A ‘Devastating Witness’)

Grassley and Johson said they are “troubled” by Bentel’s refusal “to engage with the committees even after repeated overtures of accommodation.”

They also wrote that they would hold a “voluntary and informal” meeting, but that they “will consider other options if faced with a continuing lack of cooperation.”

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