By Bill SammonManaging Editor, Washington Bureau, FOX News Channel

Acknowledging that "an apology is owed," Homeland Security Secretary Janet Napolitano promised Thursday to "meet and clear the air" with veterans groups that were offended by her agency's report citing "returning veterans" as terrorist risks to the U.S.

"To the extent veterans read it as an accusation," Napolitano told FOX News, "an apology is owed."

"I'll meet with the leaders of some of the veterans groups," she promised on "FOX Friends." "The last thing we want to do is offend or castigate all veterans. To the contrary, let's meet and clear the air."

"Let me be very clear," Napolitano told FOX News. "If there's one part of that report I would re-write -- in the wordsmithing, Washingtonese that goes on after the fact -- it would be that footnote."

"I'm not running away from it," she added. "But I will say it was an assessment -- it was not an accusation."

Napolitano said she was briefed on the report, including the warning about returning veterans, before it was released.

"I have to tell you, I was the United States Attorney for Arizona in the 90's when Tim McVeigh bombed the Murrow building in Oklahoma City and unfortunately he was a vet -- that's where he got his training," she said. "And so when I was told about the report, it rang true with me. This has happened in the past."

In January, DHS issued a warning about "left wing extremists."

"On the other side of the political spectrum, for example, we have the same in the animal rights category," Napolitano told FOX. "We have a very, very active community, in the United States, for the protection of animal rights. But occasionally -- very rarely, but it does happen, you know it happens -- it spills into violence."