In the midst of the worst crisis at NBC News in decades, Brian Williams just announced that he will remove himself from "Nightly News" for "the next several days" as the internal investigation into his reporting gets underway. 

His statement, released about 4:15 p.m. Saturday, reads: "In the midst of a career spent covering and consuming news, it has become painfully apparent to me that I am presently too much a part of the news, due to my actions. As Managing Editor of NBC Nightly News, I have decided to take myself off of my daily broadcast for the next several days, and Lester Holt has kindly agreed to sit in for me to allow us to adequately deal with this issue. Upon my return, I will continue my career-long effort to be worthy of the trust of those who place their trust in us."

 Williams has been enveloped in a firestorm since Wednesday, when he announced on the air that he had mistakenly said that during the opening days of the Iraq War, he was in a helicopter that had been forced to land after it was hit by a rocket-propelled grenade. He told the story as recently as last week, this time on "Nightly News" -- although he stopped short of apologizing for numerous other instances of relating the story.

Then, on Friday, the New Orleans Advocate published a story questioning Williams' reporting during Hurricane Katrina. Other media outlets, including The Washington Post, have cited other discrepancies — including his assertion that he had seen a man jump to his death inside the Superdome, while in another instance said "we had all heard" of the suicide.

NBC on Friday began an internal investigation although it was unclear exactly what the investigation team hoped to turn up, or when it would conclude its work.

Williams has been silent since Wednesday, and this statement marks his first public acknowledgment of a crisis that now threatens his career. Indeed, NBC News staffers Friday  speculated on various scenarios if Williams were forced to step down. Some of those are considered unlikely — a brief return to the anchor chair by Tom Brokaw — and some considered logical. Lester Holt, a well-liked figure inside NBC News, was considered the most logical choice as temporary replacement. The question that many inside NBC News will be asking over the next few days: Could Holt become the permanent replacement too?