Elizabeth O’Bagy, a pro-Syrian opposition analyst whose credibility has come under fire, might have even more explaining to do – as court documents show she once vouched for a rebel group whose website displayed extremist and anti-American images.

Among the pictures was one showing a burning U.S. Capitol.

O’Bagy was fired earlier this week by the Institute for the Study of War for allegedly lying about her academic credentials. Her writings had been used by U.S. officials to bolster their case for military action against the Assad regime.

O’Bagy discussed the rebel group in question in a June 19, 2013 signed affidavit filed in the case of American Eric Harroun, who was indicted for fighting alongside the terror group al-Nusra in Syria.

O’Bagy’s signed declaration, which included a breakdown of rebel groups and their varying degrees of affiliation to Al Qaeda-linked terrorists, was used by Harroun’s defense to argue that the former Army medic had actually fought with a splinter group and not a terrorist one – a group tied to the one O’Bagy described.

In the document, O’Bagy said she had reviewed the apparent Facebook page for the Al Aqsa Islamic Brigades, and found no signs of jihadist leanings.

“I have also reviewed a Facebook site … that purports to be associated with the al Aqsa (Islamic) brigades,” she stated in the affidavit. “The facebook site does not appear to be particularly jihadist in orientation, and posts videos associated with groups that are all affiliated with the Free Syrian Army.”

Yet newly uncovered images from the group’s Facebook page depict otherwise – including one that shows the U.S. Capitol building engulfed in flames, and armed fighters marching in the foreground. Other images show what appears to be a black-and-white flag, which is viewed by intelligence analysts as a sign of a group’s Islamist bent (although O’Bagy wrote that many fighters not affiliated with jihadist groups use a similar flag).

The Facebook postings, which had been up for weeks, were recently taken down following an NBC News investigative report about the group.

O’Bagy said in the court document that there are several groups that go by the name of Al Aqsa. But the Facebook site she referenced in the affidavit is the same one that contained the extremist images – although it’s possible she never saw those pictures.

O’Bagy, a Georgetown University alumna, was put in the media spotlight following an op-ed piece she wrote in The Wall Street Journal which was cited by Secretary of State John Kerry and Sen. John McCain, R-Ariz., in their case for a military strike in Syria.

Specifically, Kerry read a quote from the op-ed in which she wrote that Islamic extremist factions are not "spearheading the fight against the Syrian government," but rather that the struggle is being led by "moderate opposition forces."

Since then, O’Bagy has appeared on multiple news outlets, including Fox News, CNN and NPR, to discuss Syria. She has weighed in on complicated ethnic and religious challenges in the region.

Her credibility and objectivity came into question over her work with a Syrian opposition group called the Syrian Emergency Task Force.

The Journal, after the op-ed was first published, included a clarification noting she is "affiliated" with that group, and that the organization subcontracts with the U.S. and British governments "to provide aid to the Syrian opposition."

O'Bagy, in an interview last week on Fox News, claimed she is not an employee of the task force, and is not a lobbyist. She said she works with them as an independent contractor, and her contract fee comes through U.S. government contracts.

She also defended herself on Twitter, claiming she is "not paid to advocate" the view that the U.S. should get involved in Syria.

The D.C.-based scholar was fired this week from the Institute for the Study of War for allegedly lying about her education credentials.The institute posted a statement on its website claiming she misled the organization about having a Ph.D.She reportedly claims she had defended her dissertation, but was waiting for the degree.

Calls to O’Bagy from FoxNews.com on Thursday were not returned.