Director of National Intelligence James Clapper testified before Congress today that al Qaeda and Sunni extremists were seeking to gain influence in Syria,  possibly infiltrating some of the fragmented opposition groups engaged in fighting there.

"Another disturbing phenomenon that we've seen recently, apparently, is the presence of extremists who have infiltrated the  opposition groups,"  Clapper told members of the Senate Armed Services Committee.

"The two bombings in Damascus in December … and then the two additional bombings in Aleppo, both of which were  targeted against security and intelligence buildings … had all the  earmarks of an al Qaeda-like attack.  So we believe that al Qaeda in Iraq is extending its reach into Syria." Clapper said.

"The state of the opposition, which is quite fragmented, it's very localized - the Syrian National Council really doesn't … command and control these oppositionist groups," Clapper said.

Lt. Gen. Ronald Burgess, the director of the Defense Intelligence Agency, said that U.S. intelligence has not yet determined if foreign al Qaeda-linked fighters have been coming into Syria to join the fight.

"What we haven't seen so  far, and what we have not assessed yet is, whether there would be what I would call a clarion call to outsiders coming in to augment," Burgess said. "We haven't seen much of that up to this time.  So basically, the team  that's on the ground is playing with what it has."

Following the hearing, Secretary of Defense Leon Panetta was asked what al Qaeda's presence might mean for U.S. interests in Syria.   Panetta said he was concerned, but that more information was needed.

"It means that I think we have to continue to work  with the Arab League and determine what steps should be taken to try to deal with the situation in Syria," he said. "It does raise concerns for us  that al Qaeda is trying to assert a presence there. And that means that, you know, frankly, our concerns, which were large  to begin with because of the situation, the deteriorating situation in  Syria, that the situation there has become that much more serious as a result of that."

Asked if the U.S. can support a Syrian opposition that includes al Qaeda, Panetta said, "I think a lot remains to be seen as to  exactly what their role is before we come to that conclusion.  I  think, you know, just the fact that they're present concerns us.  As to what their role is and how extensive their role is, I think that  still remains to be seen."

Clapper told the committee that although core al Qaeda has suffered heavy losses in the past year, officials remain very concerned about the reach of the regional groups.

"While we have made important gains [against] al Qaeda and its affiliates, we remain in a race against their ability to  evolve, regenerate leadership and launch attacks."

Towards the end of the hearing, Clapper added that he was concerned that despite key ideological differences between Sunni and Shia Islam, Iran could reach out to al Qaeda to use it as a proxy force.

Clapper called the relationship between elements in Iran and al Qaeda a "shotgun marriage," given that Iran has harbored some senior al Qaeda leaders under the guise of "house arrest."

"They have had this sort of stand off arrangement with al Qaeda, allowing them to exist there, but not to foment any operations directly from Iran, because they're very sensitive about, 'Hey, we might come after them there as well.'" Clapper said.  "So there has been this longstanding, as I say, kind of, shotgun marriage, or marriage of convenience. I think, probably, the Iranians may think that they might use, perhaps,  al Qaeda in the future as a surrogate or proxy."

Clapper cited al Qaeda in the Arabian Peninsula (AQAP) as the greatest al Qaeda threat, telling the committee, "AQAP … we view as the primary threat to the homeland because of their planning and intent to attack either in Europe or homeland of the United States."