Matt Lauer fired from NBC News after complaint about 'inappropriate sexual behavior'

Matt Lauer was fired from NBC News on Wednesday after an employee filed a complaint about "inappropriate sexual behavior in the workplace," the network announced.

Savannah Guthrie made the announcement at the top of the "Today" show. "We are devastated," she said.

The "Today" show is one of the most popular and most profitable franchises on American television. Lauer was the cornerstone of the program for two decades.

So his sudden ouster came as a shock to viewers -- but not as a complete surprise to his "Today" show colleagues. They knew that multiple news outlets were investigating Lauer's off-camera conduct.

NBC News chairman Andrew Lack said in an early morning memo to staff that the complaint was filed on Monday night. Lack said it was the first complaint lodged against Lauer in his career at the network. But he also said "we were also presented with reason to believe this may not have been an isolated incident."

Indeed, Lack and other NBC News executives have known for weeks that damaging stories could be coming out soon.

Reporters for The New York Times have been investigating Lauer for weeks, according to sources who had been contacted by the Times.

And Variety's New York bureau chief Ramin Setoodeh said on Twitter that he and his colleague Elizabeth Wagmeister have been doing reporting "about serious sexual harassment allegations against Lauer" for two months.

"NBC was aware" of the reporting, Wagmeister tweeted. "There are multiple women we've spoken to with far-ranging accusations against Lauer. The power of journalism has never been more evident with this cultural change."

An NBC News spokeswoman declined to comment beyond the information in Lack's memo.

A spokeswoman for Lauer said he has no comment at this time. Lauer may release a statement later on Wednesday.

Lauer was informed of the network's decision late Tuesday night, before he went to bed, according to a source with knowledge of the situation.

And Guthrie, his co-host for the past five years, was told overnight.

"We were both woken up with the news kind of predawn," Guthrie's co-host Hoda Kotb said. "And we're trying to process it and make sense of it. And it will take some time for that."

Related: Read Andrew Lack's memo to NBC staff

Lauer is the latest high-profile man in media to be brought down by allegations of inappropriate sexual behavior. Just last week, CBS News fired one of its own morning anchors, Charlie Rose, after a report in The Washington Post chronicled years of alleged sexual misconduct on his part.

The torrent began when The New York Times and The New Yorker reported on allegations against the Hollywood producer Harvey Weinstein.

Since then, actors Kevin Spacey and Louis C.K. have been suspended or removed from projects after allegations against them became public. And other prominent journalists, including Mark Halperin of NBC and Michael Oreskes of NPR, have been fired or suspended from their jobs.

Related: CBS News and PBS fire Charlie Rose

The firing of Lauer removes one of the most recognizable personalities on television at a time when morning news programs are increasingly important to network news divisions.

"This is a sad morning at 'Today' and NBC News," Guthrie said at the top of the 7 a.m. hour. "As I'm sure you can understand, we are devastated. I'm heartbroken for Matt."

Guthrie also said she was heartbroken for the woman who accused Lauer of misconduct, noting "it's long overdue" that women feel comfortable coming forward against abusive men.

Hoda Kotb, on the set with Guthrie, said she has known Lauer for years and "loved him as a friend and a colleague."

"It's hard to reconcile the man who walks in every day" with the person who was identified in the complaint, she said.

Lauer, 59, was named a co-anchor of "Today" in January 1997 after three years as the newsreader.

He co-anchored NBC's coverage of the September 11, 2001 terrorist attacks and other historic news events.

His contract calls for him to be paid tens of millions a year. It reportedly ran through 2018.

--CNNMoney's Jill Disis, David Goldman and Chris Isidore contributed to this report.