A highly sought witness in the Benghazi investigation was scheduled to testify Thursday morning behind closed doors in Congress, WND has learned.

No word yet on whether he appeared or what he may have said before a closed session of the House Intelligence Committee.

Marine Col. George Bristol is considered a key witness because he may be able to shed light on why no U.S. military help was sent when the U.S. mission in Benghazi, Libya, came under attack on Sept. 11, 2012.

The U.S. ambassador to Libya, Christopher Stevens, and three other Americans died in the attack.

Congressional investigators have been trying to locate Bristol for months. As commander of Joint Special Operations Task Force-Trans Sahara, he knew what military options the U.S. had when the compound in Benghazi came under attack.

Investigators could not find him because Defense Department officials told members of Congress he had retired in March and could not be forced to testify.

However, about a week ago, the Marine Corps Times discovered Bristol had not retired .

The paper quoted Marine spokeswoman Maj. Shawn Haney as saying Bristol would be on active duty through the end of July.

That contradicted statements Pentagon officials had issued to both Congress and the media.

A member of Congress told WND it was imperative to find Bristol before he retires at the end of the month, in case the colonel is forced to sign a non-disclosure agreement upon leaving active duty.

WND located Bristol and passed his contact information on to  Congress.

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