NBC News anchor Brian Williams has announced that he will take a leave of absence from the network, as NBC launches an internal investigation, which stemmed from Williams’ revelation that he lied about being on a helicopter that was shot down by RPG fire during invasion of Iraq in 2003.

On Saturday, NBC News released Williams’ announcement regarding his hiatus. In the statement, Williams said he has decided to take a leave of absence for “the next several days” and that NBC News anchor Lester Holt will take his place:

“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’ news comes after NBC announced on Friday that it will be conducting an internal investigation regarding a report Williams gave about his time spent covering the invasion of Iraq in 2003.

The Associated Press reported that the probe will be led by Richard Esposito, who worked at ABC, the New York Daily News and New York Newsday prior to coming to NBC.

NBC News President Deborah Turness announced the investigation in an internal memo on Friday:

“As you would expect, we have a team dedicated to gathering the facts to help us make sense of all that has transpired. We’re working on what the best next steps are.”

New York Times columnist Maureen Dowd wrote an editorial on Saturday claiming, “NBC executives were warned a year ago that Brian Williams was constantly inflating his biography.”

“THIS was a bomb that had been ticking for a while,” wrote Dowd. “But the caustic media big shots who once roamed the land were gone, and ‘there was no one around to pull his chain when he got too over-the-top,’ as one NBC News reporter put it.”

Williams issued a public apology on Wednesday, for a report he gave on Jan. 30, in which he claimed that he was onboard a helicopter that was shot down by RPG fire during the invasion of Iraq in 2003.

In the original report, Williams stated that he was in the helicopter behind the one that was “almost blown out of the sky” by an RPG.

In 2007, during an interview with Emily Fitzmaurice at Fairfield University, Williams listed his coverage of Iraq as one of the stories that has had the biggest impact on his life. He claimed that he “looked down the tube of an RPG that had been fired,” and had hit the chopper in front of the one he was in.

Williams’ story changed in 2013, during an interview on Late Night with David Letterman, when he said, “two of our four helicopters were hit by ground fire, including the one I was in.”

Although the 2013 version of the story was false, Williams repeated it again on a broadcast of NBC Nightly News on Jan 30. Williams stated that the helicopter he was flying in was “forced down after being hit by an RPG.”

Williams admitted his mistake after being called out on Facebook by soldiers who were on board the Chinook helicopter that was hit. He responded to one of the comments, and admitted that he “was in fact on the Chinook behind the bird that took the RPG in the tail housing just above the ramp.” Williams then issued a public apology on Wednesday, claiming that he had “misremembered” the exact details of what had occurred during his time in Iraq.

The claim that Williams was in a helicopter that was in the same formation as the one that was shot down has been contested by crew members on board the helicopter, who told Stars and Stripes that Williams arrived at the scene an hour after the helicopter made its emergency landing, and only stayed for a few minutes to take pictures and to talk to the crew members.

With Williams’ credibility as a journalist being called into question, there is speculation he also lied about his coverage of Hurricane Katrina.

The New Orleans Advocate reported that the claim Williams made of watching a dead body “float by face down” from his hotel room window in the French Quarter is not possible, due to the fact that the French Quarter is the “original high ground of New Orleans,” and “was not impacted by the floodwaters that overwhelmed the vast majority of the city.”

According to the Associated Press, NBC News “refused to comment Saturday on when or whether Williams would return and who would decide his future.”

Feb. 9, 2015: UPDATE: Brian Williams’ Coverage of Rocket Fire in Israel Raises Questions

Feb. 10, 2015: UPDATE: NBC Suspends Brian Williams for 6 Months without Pay