WASHINGTON — The highest ranking American diplomat in Libya who survived the attack that killed U.S. Ambassador Chris Stevens and three other Americans last year testified Wednesday that he was pressured not to meet with congressional investigators after the attack.

Gregory Hicks, a foreign service officer and former deputy chief of mission/chargé d’affairs in Libya, also testified that Cheryl Mills, a top aide to Secretary of State Hillary Clinton, became upset with him for cooperating with the investigators without having State Department lawyers present.

The revelation led Ohio Rep. Jim Jordan to accuse the Clinton and her aides of a “cover-up.”

“Here’s a guy with 22 years of outstanding service to our country,” Jordan said. “Twenty-two years. Outstanding service. Praised by everybody who counts — the president, the secretary, every one above him. And yet now they’re obstructing him because he won’t help them cover this up.”

“He’s an honorable man here telling the truth,” Jordan said. “Now he’s getting this kind of treatment from the very people who praised him before. This is why this hearing is so important.”

Here’s the exchange between Jordan and Hicks about Utah Rep. Jason Chaffetz’s trip to Libya and the phone calls he received from State Department attorneys.

Jordan: Tell me about those conversations. What those lawyers instructed you to do on Mr. Chaffetz’s visit to Libya.

Hicks: I was instructed not to allow the RSO [Regional Security Officer], the acting deputy chief of mission and myself to be personally interviewed by Congressman Chaffetz.

Jordan: So the people at state told you, “Don’t talk to the guy who is coming to investigate?”

Hicks: Yes, sir.

Jordan: You’ve had several congressional delegations come to various places you’ve been around the world. Has that ever happened? … Have you ever had anyone tell you don’t talk with the people from Congress coming to find out what took place?

Hicks: Never.

Hicks testified that Mills was upset with Hicks because State Department attorneys were not allowed in his meeting with Chaffetz because they didn’t have the proper security clearance.

Jordan: You had another conversation on the phone with Cheryl Mills. Tell me, who is Cheryl Mills?

Hicks: She’s counselor for the Department of State and chief of staff to Secretary Clinton.

Jordan: That’s a pretty important position?

Hicks: Yes, sir.

Jordan: When she calls, you take the phone call? … She’s a fixer for the secretary of state. She is as close as you can get to the Secretary Clinton? Is that accurate?

Hicks: Yes, sir.

Jordan: And tell me about that phone call you had with Cheryl Mills.

Hicks: A phone call from that senior person is generally speaking not considered to be good news.

Jordan: What did she have to say to you?

Hicks: She demanded a report on the visit. … She was upset.

Hicks — referred to as a “whistle-blower” — testified with two other witnesses during the House Committee on Oversight and Government Reform’s “Benghazi: Exposing Failure and Recognizing Courage” hearing.

At the beginning of the hearing, Hicks stated: “I am a career public servant. Until the aftermath of Benghazi, I loved every day of my job.”

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