NEW YORK — Even as Matt Lauer apologized for sexual misconduct and NBC prepared for life without him at the “Today” show Thursday, questions lingered about who knew about his behavior and whether women at the network could have been protected.

Lauer was fired late Tuesday after an NBC employee detailed what NBC News chief Andrew Lack described as Lauer’s “inappropriate sexual behavior” that began at the Sochi Olympics in 2014. Two other women came forward Wednesday with complaints, with one telling The New York Times that Lauer had sexually assaulted her in his office in 2001. A Variety magazine investigation outlined a pattern of alleged salacious behavior, including three women who said Lauer harassed them.

Lauer’s first public response to his firing was read by his former co-host, Savannah Guthrie, on “Today” Thursday.

“I regret that my shame is now shared by the people I cherish dearly,” Lauer said in the statement. “Repairing the damage will take a lot of time and soul searching and I’m committed to beginning that effort. It is now my full-time job.”

Lack said Monday’s complaint was the first one management had received about Lauer. In private meetings with NBC staff, he and top deputy Noah Oppenheim — former executive producer at “Today” — stressed they were unaware of the activity. According to Variety, several women said they complained to NBC executives about Lauer’s behavior, but their concerns “fell on deaf ears” because the show — which consistently ranks 2nd among the morning lineups — is so important to the network financially. The women spoke to the magazine under condition of anonymity.

After the Variety story was posted and NBC received the additional complaints, the network stressed that no one in “current” NBC News management had been aware of Lauer’s behavior.

CNN chief executive Jeff Zucker, who was executive producer of “Today” in the 1990s and eventually rose to head of NBC Universal, said at a business conference on Thursday that “there was never even a whisper” of suggestion that Lauer was engaged in deviant or predatory behavior.

“I’ve known Matt for 25 years and I didn’t know this Matt,” Zucker said at Business Insider’s Ignition conference. He called the news “incredibly, incredibly heartbreaking.”

People within the industry said there had been talk of alleged infidelity — Lauer’s wife once filed for divorce but it was withdrawn — but not of harassment. Yet on MSNBC’s “Morning Joe” on Thursday, co-host Mika Brzezinski said that “when the story broke, to be very honest, I was not shocked.”

Her co-host and fiance, Joe Scarborough, said he attended a Friar’s Club roast of Lauer a few years ago where sex was an omnipresent topic.

“The whole theme was that he does the show and then he has sex with people, with employees,” he said. “So was this whispered behind closed doors? No. It was shouted from the mountaintops and everybody laughed about it.”

Lauer said in his statement that some of what has been said about him is untrue or mischaracterized, “but there is enough truth in these stories to make me feel embarrassed and ashamed.” He did not specify which allegations were true or untrue.

“The last two days have forced me to take a very hard look at my own troubling flaws,” he said. “It’s been humbling.”

NBC would not comment on Thursday about what steps the network would take to explore the extent of knowledge about Lauer’s behavior. The New York Daily News, which said in an editorial that NBC “feigned surprise” about Lauer’s behavior, called on corporate parent Comcast to order an independent investigation. “Dig deep, find the facts, expose and discipline all those who ran interference for a harasser,” the newspaper said.

Next up for the network is deciding how to suddenly replace a man who had been co-host for two decades. CBS News faces the same task, after Charlie Rose was fired last week following sexual misconduct charges.

Willie Geist, Craig Melvin and Al Roker are three in-house possibilities at NBC, and Vladimir Duthiers has subbed for Rose since his firing. Given the climate in the country with the rush of sexual misconduct cases, having all women in the primary roles looms as an interesting possibility. That’s a rarity in morning news where, with the exception of the Robin Roberts-Diane Sawyer pairing at “Good Morning America” last decade, there’s usually at least one man as a host.

Hoda Kotb co-hosted with Guthrie at “Today” for the two days since Lauer’s firing. Megyn Kelly is another possibility, but since she just started her 9 a.m. show this fall, a move for her is less likely. Along with Duthier, CBS’ Bianna Golodryga is lined up as a fill-in for Rose with the team of Gayle King and Norah O’Donnell on “CBS This Morning.”

Kate O’Brian, a news consultant and former ABC News executive, said networks shouldn’t necessarily rush into an all-woman cast, even though women make up the majority of viewers for network morning shows.

“The whole point is not to take men away from it,” she said. “The point is that men and women should be able to work in a workplace free of harassment.”