The network's internal fact-checking investigation is "nowhere near done," a senior NBC source told CNN Thursday.
It has widened beyond just Williams' initial errors about a 2003 Iraq War mission to include other possible misstatements, but the network has not commented on any particular ones.
When he apologized last week for his on-air error about the Iraq mission, he chalked it up to innocent "misremembering." But others have implied something more malicious.
On Thursday The Huffington Post identified questions about Williams' claims of flying into Baghdad with SEAL Team 6 and about "war memorabilia the anchor claims to have received as gifts, including a Navy SEAL's knife and a piece of the helicopter from the raid that killed Osama bin Laden."
CNN analyst Peter Bergen said on "Anderson Cooper 360" that he was told by sources in the Seal community that it would be impossible for Williams to have ever traveled with Seal Team 6.
"We do not embed journalists with any elements of that unit ... bottom line -- no," one Special Operations Command official said.
In the case of the memorabilia that Williams says he received from "his friends" in the Seal community: "that doesn't pass any sniff test," another Seal officer told Bergen.
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