The Department of Defense is looking into ways to "pump up the security" for the team of Navy SEALs who helped kill Osama bin Laden after the commandos expressed concern for their safety and the safety of their families, Defense Secretary Robert Gates said Thursday.

Gates made the comment in response to a question at a town hall meeting at Camp Lejeune, North Carolina. A Marine asked what measures were being taken to protect "the identities and the lives" of the SEALs involved in the takedown of bin Laden in Pakistan a week ago, as well as other troops deployed in the region, from the threat of retaliation.

"We are very concerned about the security of our families - of your families and our troops, and also these elite units that are engaged in things like that. And without getting into any details ... I would tell you that when I met with the team last Thursday, they expressed a concern about that, and particularly with respect to their families," Gates told the audience.

"Frankly, a week ago Sunday, in the Situation Room, we all agreed that we would not release any operational details from the effort to take out bin Laden. That all fell apart on Monday, the next day."

Gates' comments offered the first insight into the mindset of the team members since they carried out the risky operation.

SEALs, short for Sea, Air and Land teams, are known as "quiet professionals." They keep a low profile because of the classified nature of their tactical operations.

The team, known as SEAL Team 6, is widely believed to have returned to American soil. But the unit is covered with such a degree of secrecy that the military won't confirm its presence.

The Marine's question underscored sentiment among military and intelligence communities that identification of the team signified an unprecedented breach of confidentiality.

Gates acknowledged the threat of retaliation against Team 6 and troops deployed in the region.

"There is an awareness that the threat of retaliation is increased because of the attacks - because of the action against bin Laden," he said. "The one thing I would tell you, though, is that I think there has been a consistent and effective effort to protect the identities of those who participated in the raid, and I think that has to continue."

A Pentagon spokesman later cautioned against interpreting Gates' response "as a criticism of any particular person or office."

"He was indeed voicing his concern about the breakdown in operational security after the killing of Bin Laden," Deputy Assistant Secretary of Defense Geoff Morrell said. "Anonymous sources revealing secret information about the tactics, training, and equipment of covert forces put at risk our ability to successfully mount similar missions in the future."