A group of employees contends that different points of view aren’t tolerated at Facebook.

SAN FRANCISCO — The post went up quietly on Facebook’s internal message board last week. Titled “We Have a Problem With Political Diversity,” it quickly took off inside the social network.

“We are a political monoculture that’s intolerant of different views,” Brian Amerige, a senior Facebook engineer, wrote in the post, which was obtained by The New York Times. “We claim to welcome all perspectives, but are quick to attack — often in mobs — anyone who presents a view that appears to be in opposition to left-leaning ideology.”

Since the post went up, over 100 Facebook employees have joined Amerige to form an online group called FB’ers for Political Diversity, according to two people who viewed the group’s page and who were not authorized to speak publicly. The aim of the initiative, according to Amerige’s memo, is to create a space for ideological diversity within the company.

The new group has upset other Facebook employees, who said its online posts were offensive to minorities. One engineer, who declined to be identified for fear of retaliation, said several people had lodged complaints with their managers about FB’ers for Political Diversity and were told that it had not broken any company rules.

Another employee said the group appeared to be constructive and inclusive of different political viewpoints. Amerige did not respond to requests for comment.

The activity is a rare sign of organized dissent within Facebook over the company’s largely liberal workplace culture. While the new group is just a sliver of Facebook’s workforce of more than 25,000, the company’s workers have in the past appeared less inclined than their peers at other tech companies to challenge leadership, and most have been loyalists to CEO Mark Zuckerberg.

But over the past two years, Facebook has undergone a series of crises, including the spread of misinformation by Russians on its platform and the mishandling of users’ data. Facebook has also been accused of stifling conservative speech by President Donald Trump and Sen. Ted Cruz, R-Texas, among others. The social network recently barred far-right conspiracy theorist Alex Jones, which critics seized on as further evidence that Facebook harbors an anticonservative bias.

Within Facebook, several employees said, people have argued over the decisions to ban certain accounts while allowing others. At staff meetings, they said, some workers have repeatedly asked for more guidance on what content is disallowed and why. Others said Facebook, out of fear of being seen as biased, has let too many right-wing groups flourish on the site.

The dispute over employees’ political ideology arose a week before Sheryl Sandberg, Facebook’s chief operating officer, is scheduled to testify at a Senate hearing next Wednesday about social media manipulation in elections. A team helping Sandberg get ready for the hearing has warned her that some GOP lawmakers may raise questions about Facebook and biases, according to two people involved in the preparations.