The comments came in response to CNN's apology and retraction of a story published late last week, after the network discovered numerous issues with the piece. Three journalists who worked on the story also resigned.
Sanders spent nearly two minutes in an uninterrupted answer — her first of the briefing — calling into question CNN's credibility, although she did not name the network. She also encouraged people to watch a video purportedly showing a CNN employee, who was not responsible for the network's coverage of the Russia investigation, criticizing the network.
“There's a video circulating right now whether it's accurate or not, I don't know, but I would encourage everybody in this room and frankly everybody across the country to take a look at it,” Sanders said. “If it is accurate, I think it is a disgrace to all of media, to all of journalism.”
Sanders was following through on a line of attack against CNN — which has frequently been in the administration's crosshairs — that President Trump began in tweets on Tuesday morning.
“Wow, CNN had to retract big story on 'Russia,' with 3 employees forced to resign. What about all the other phony stories they do? FAKE NEWS!” Trump wrote.
CNN's apology was accepted by Anthony Scaramucci, a former Trump transition official who was the subject of the retracted piece. Asked why the apology was not acceptable to the president, Sanders did not answer directly.
“I think it's the constant barrage of fake news directed at this president [that] has probably garnered his frustration,” Sanders said.
She later criticized news outlets, which she claimed reported stories based on anonymous sources, of having “no sources at all.”
“I think that we have gone to a place where if the media can't be trusted to report the news, then that is a dangerous place for America,” Sanders said.
At one point, Sanders was confronted by a reporter in the room who accused her of “inflaming” a story despite the network's efforts to retract and rectify the problem.
“First of all, I think if anything has been inflamed, it's the dishonesty that often takes place by the news media,” Sanders said.
In all, the criticism against the media ate up nearly five minutes of a 17-minute question-and-answer session by the spokeswoman.
Reporters had already sat through a 40-minute briefing by Energy Secretary Rick Perry about the White House's “energy week.”
But on a day that Senate Republicans postponed indefinitely a vote on their health-care bill, Sanders opened the briefing with a dry pronouncement that the Affordable Care Act, or Obamacare, is collapsing.
“The president is optimistic that Republicans will live up to the promise that they've been making to the American people for seven years by repealing and replacing Obamacare,” Sanders said before minutes later launching into her critique of the media.
Even after the White House issued an opaque threat to Syrian President Bashar al-Assad on Monday night to discourage him from using chemical weapons against his people, that issue seemed to provoke less outrage from Sanders.
“The message from the statement yesterday was extremely clear,” Sanders said. “I think it was pretty black and white.”
The contentious session also comes after weeks of tensions with the White House press corps over a push to make the briefings off camera, and in some cases, not have briefings at all.
Shortly before closing out Tuesday's briefing, Sanders took a question from a reporter with LifeZette, the conservative website founded by radio host Laura Ingraham — who has been considered as a potential candidate to be Trump's White House press secretary.
The reporter offered Sanders an opportunity to name other stories that the White House would like to see retracted.
“I think that'd be a great idea,” Sanders said gamely without naming any specific stories that she would like to see retracted. “I certainly don't think you'd get an argument from us if there were retractions from outlets on fake stories.”
As she walked out of the briefing room and into the West Wing, a CNN reporter called out requesting to ask a question after being criticized for much of the briefing.
Sanders disappeared behind the blue doors without answering.