As investigations widen in the case of the recent assault in Benghazi that left US Ambassador John Stevens and three other Americans dead, new intelligence suggests the attack was tied to al-Qaeda, and particularly an associate of Osama bin Laden.

It has been suggested ever since the September 11, 2012 attack in Benghazi that terrorists may have been behind the raid that killed four Americans, including Mr. Stevens and a Navy SEAL, but this week the claim was heard by Congress as US lawmakers attempt to get to the bottom of the incident.

“Yes, they were killed in the course of a terrorist attack on our embassy,” Matt Olsen, director of the National Counterterrorism Center, said during a Senate hearing Wednesday, Fox News reports.

Separately, a source close with Mr. Stevens tells CNN this week that the ambassador insisted before his death that he believed he was on an al-Qaeda hit-list.

In the immediate aftermath of the assault earlier this month, US officials explained that an anti-Islamic video uploaded to YouTube, ‘Innocence of Muslims,’ was the impetus behind protests across the Arab World, which pinnacled with the storming of a US consulate building in Benghazi on September 11. On Tuesday this week, White House Press Secretary Jay Carney told reporters, “We have provided information about what we believe was the precipitating cause of the protest and violence based on the information that we have had available,” and that the US stands by the claim that “spontaneous” attacks on the consulate resulted in the loss of four Americans. Conflicting reports in the days since suggest that the assault was not a spontaneous violent demonstration as originally described, however, and that the attack may have very well been thought out in advance and plotted to commemorate the eleventh anniversary of the attack on the World Trade Center.

“We are looking at indications that individuals involved in the attack may have had connections to al-Qaeda or al-Qaeda’s affiliates, in particular al-Qaeda in the Islamic Maghreb,” Mr. Olsen claimed this week before the Senate Homeland Security Committee. “I would say yes, they were killed in the course of a terrorist attack on our embassy,”

Fox News adds in their report that so far the finger is being pointed at 53-year-old Sufyan Ben Qumu, a veteran of the Libyan Army who has previously been interned at America’s military prison at Guantanamo Bay, Cuba over accusations that he was linked with al-Qaeda. Qumu was released from Gitmo in 2007 despite being considered a threat by American authorities, and sent back to Libya, where he was promised to be held behind bars. The regime of former leader Muammar Gaddafi later released him from the facility, after which the Daily Mail says he “emerged as a leader of the rebels” that attempted to overthrow Gaddafi’s very government.

Before being captured by US forces shortly after the 2011 invasion of Afghanistan, Qumu is thought to have aided Taliban fighters and worked for a charity believed to be an al-Qaeda front. He has also been labeled as a one-time personal driver for Osama bin Laden, although Qumu has denied that allegations. Now he is being considered a suspect in last week’s assault.

On Wednesday, Libyan Prime Minister Mustafa A.G. Abushagur said that Mr. Steven’s effort overseas “played a key role in helping to liberate Libya from the oppressive regime of Muammar Gaddafi.”