(John Gress/Getty Images)

Two of Newsweek’s top editors — editor in chief Bob Roe and executive editor Kenneth Li — were abruptly fired from the company on Monday, along with reporter Celeste Katz.

The decision caused chaos among the newsroom’s remaining employees, who first found out about the firings not from management, but through word of mouth. Two reporters at Newsweek and its sister publication, the International Business Times, have since resigned in protest.

Katz, Roe and Li were among a team of reporters and editors who were pursuing an investigative piece into the finances of Newsweek’s parent company, the Newsweek Media Group. The company publishes Newsweek, the International Business Times and a handful of other websites.

Newsweek Media Group declined to comment on “personnel matters,” but at least one person familiar with the matter said that internally, the pieces were easy to put together: “These reporters and editors had launched an investigation,” the person said, “and now they’re no longer there.”

According to an internal memo obtained by CNN and HuffPost, International Business Times managing editor Nancy Cooper will serve as acting editor of Newsweek. The memo also confirms that Roe and Li were “leaving the business.”

Employees were told to stop work and given the option of going home early on Monday, but some stayed, hoping to learn more about why the magazine’s top editors were suddenly fired, one current employee of Newsweek Media Group said. Others were anticipating the worst and started downloading their clips, brushing up resumes and preparing to look for work elsewhere in the event that the entire publication collapsed.

On Tuesday, Cooper began her first day as acting editor with a brief address to newsroom employees, according to the Newsweek Media Group employee. Cooper said that the magazine would continue publication, and took a few questions from the staff. When some reporters attending the meeting expressed interest in picking up Katz’s investigative work into Newsweek Media Group, editors discouraged them from doing so, for fear they, too, would be fired.

Matthew Cooper, a senior writer at Newsweek, resigned from the company in protest of the firings on Monday.

Cooper called the firings a “disgrace,” writing that in his 30-year tenure as a journalist, “I’ve never seen more reckless leadership.”

On Tuesday morning, David Sirota, another Newsweek and IBT reporter announced his resignation. “I am proud of my nearly 4 years there, producing serious award-winning investigative journalism under extremely difficult circumstances,” Sirota tweeted.

“The challenges facing the organization made it a very difficult working environment and so it became clear that it is time for me to look for a new opportunity,” Sirota explained in an email to The Washington Post, shortly after announcing his resignation.

The firings were just the latest signs of trouble at Newsweek. Before she was fired, Katz was a byline on many of the magazine’s stories about what was going on at its own parent company.

Over the past month, Katz had covered the Manhattan district attorney’s raid on Newsweek’s offices, reporting that the raid was part of a months-long investigation into the Newsweek Media Group’s finances. She also covered the news that Dayan Candappa, Newsweek’s chief content officer, would take a leave of absence after BuzzFeed reported that he was the subject of a sexual harassment complaint at a previous job. Her most recent byline was on a story about the resignations of Etienne Uzac and his wife, Marion Kim. Uzac, who founded the company that became Newsweek Media Group, stepped down as chairman; Kim was the finance director.

Katz confirmed that she had been let go from the company in a tweet: “My warmest thanks to the brave Newsweek editors and colleagues who supported and shared in my work — especially our recent, difficult stories about the magazine itself — before my dismissal today. I’ll sleep well tonight … and I’m looking for a job!”

Meanwhile, those who knew the newsroom cultures at Newsweek and International Business Times before the most recent round of turmoil said that little surprised them about the firings.

“Pressure on newsroom staff to avoid commenting on IBT as a company reflects my experience there,” a former IBT employee said on Monday, adding that in their experience, employees were “encouraged not to discuss IBT’s financial situation.”

“I am not surprised by anything that happened today, and I just wish people had done the digging and reported on this story sooner,” said another former Newsweek employee, who left the company last year. “I feel very sad for the entire publication, and for the people who are still there.”

“After I was let go, I received several emails from people who had offers to work there. I told them it would be a terrible idea to take the job, that it would ruin their lives,” the former employee said, describing their last months at Newsweek as a traffic-driven, “permanent culture of fear” that led them to worry that they’d be fired at any time.

This story, originally published on February 5th, has been updated multiple times, and the time stamp changed.