Host Matt Lauer pauses during a break while filming NBC's "Today" show. (Lucas Jackson/Reuters)

On Thursday, for the second day in a row, Savannah Guthrie and Hoda Kotb opened the “Today” show with disturbing news about former host Matt Lauer, who was abruptly fired Wednesday after an allegation of sexual misconduct from an NBC employee.

“It is a difficult morning here again because our top story is once again about our former colleague, Matt Lauer,” Kotb said.

Guthrie read a just-released statement from Lauer, who said in part: "There are no words to express my sorrow and regret for the pain I have caused others by words and actions. To the people I have hurt, I am truly sorry. . . . Some of what is being said about me is untrue or mischaracterized, but there is enough truth in these stories to make me feel embarrassed and ashamed. I regret that my shame is now shared by the people I cherish dearly."

On Wednesday afternoon, Variety and the New York Times published stories that had apparently been in the works for weeks, reporting allegations of sexual misconduct from multiple women. On "Today," correspondent Stephanie Gosk said NBC News confirmed that two more women came forward to the network about Lauer.

Lauer is just one of many high-profile male celebrities accused of sexual harassment since Harvey Weinstein's downfall in early October. Hours after news about Lauer broke, former "Prairie Home Companion" host Garrison Keillor was fired from Minnesota Public Radio over an accusation of inappropriate behavior. Hip-hop mogul Russell Simmons stepped down from his companies on Thursday after a woman alleged he sexually assaulted her, which he strongly disputes.

But Lauer received the most attention in social media discussion, particularly the Variety story — in one anecdote, NBC employees told the publication that Lauer had a button under his desk that would lock his office door. “It allowed him to welcome female employees and initiate inappropriate contact while knowing nobody could walk in on him,” Variety wrote.

As Gosk detailed on "Today," the New York Times reported that a former NBC employee said Lauer sexually assaulted her in his office in 2001. Variety's piece also quoted multiple other women who alleged that Lauer had exposed himself to a colleague in his office and invited NBC employees to his hotel room while covering the Olympics through the years.

Several women “complained to executives at the network about Lauer’s behavior, which fell on deaf ears given the lucrative advertising surrounding ‘Today,’” Variety reported. “Today” reportedly brings in about $500 million in advertising per year.

The network denies prior knowledge. "We can say unequivocally, that, prior to Monday night, current NBC News management was never made aware of any complaints about Matt Lauer's conduct," NBC News said. In an earlier statement, NBC News Chairman Andy Lack said that while this was the first complaint made about Lauer's behavior in his 20 years at the network, executives had "reason to believe this may not have been an isolated incident."

CNN President Jeff Zucker, who was the "Today" show executive producer when Lauer started as co-anchor in 1997, called the allegations "incredibly disturbing" and "incredibly heartbreaking," adding he "didn't know this Matt."

"No one ever brought to me, or to my knowledge. . . . There was never a complaint about Matt," Zucker said Thursday, according to the Times, during an interview at Business Insider's Ignition conference in New York. "There was never a suggestion of that kind of deviant, predatory behavior. Not even a whisper of it."

NBC News journalists, from left: Chuck Todd, Matt Lauer, Savannah Guthrie, Megyn Kelly and Lester Holt attend an NBCUniversal event in 2017. (Evan Agostini/Invision/AP)

As “Today” grapples with its future, that question — how much executives at NBC knew — will probably keep coming up, said Robert J. Thompson, director of the Bleier Center for Television and Popular Culture at Syracuse University.

Replacing Lauer will also be a challenge, he said, as morning-show viewers are known to crave consistency and familiarity with their hosts, and — even if they're unaware it's happening — tend to form a bond with them. A good morning-show host has to be able to go into "hardcore news mode" if a breaking story happens, as Thompson put it, and the next day throw on an apron and banter with an author promoting their latest cookbook.

However, despite viewers' connection to the hosts, "Today" is powerful enough as a franchise that it could easily still thrive with a new anchor, Thompson said. The show has survived rocky transitions before, from Deborah Norville's brief tenure to Ann Curry's awkward final episode.

"The structure and format of that program are so adaptable and so versatile, and they've gone through many hosts. Although Matt was there longer than anyone, the show looks not that different from when Dave Garroway hosted" in the 1950s, Thompson said. "But you do have to put the right people in the format, and that's not as easy at it looks."

In the meantime, Lauer was spotted Thursday in the Hamptons, where his wife and three children live full-time.

“Repairing the damage will take a lot of time and soul-searching and I’m committed to beginning that effort,” Lauer said in his statement. “It is now my full-time job. The last two days have forced me to take a very hard look at my own troubling flaws. It’s been humbling. I am blessed to be surrounded by the people I love. I thank them for their patience and grace.”