CNN Business  — 

Facebook failed to take action against a self-styled militia group that was using the social media platform to encourage armed citizens to take to the streets of Kenosha, Wisconsin, on Tuesday night — despite at least one Facebook user reporting the group to the company, Facebook confirmed to CNN on Wednesday.

The group “Kenosha Guard” promoted the event “Armed Citizens to Protect Our Lives and Property.”

Facebook’s failure to act was first reported by the technology news publication The Verge.

Multiple users had reported the account for inciting violence but were told it did not violate Facebook’s rules, The Verge reported.

Seventeen-year-old Kyle Rittenhouse was arrested Wednesday following a fatal shooting in Kenosha on Tuesday night.

Facebook told CNN it had shut down Rittenhouse’s Facebook and Instagram accounts and was working with federal and local law enforcement, but it had found no evidence that Rittenhouse had followed the Kenosha Guard page or was invited to the event it had promoted.

Facebook on Wednesday said it had shut down the Kenosha Guard page for breaking its rules on militia organizations.

However, by then, the armed event Kenosha Guard was promoting had received at least 2,600 responses and had caught the attention of at least one right-wing conspiracy website.

Following a report by BuzzFeed News, Facebook later acknowledged that while it removed the militia page, it failed to remove the event being promoted by the group.

“When we responded to questions about our initial investigation into what happened in Kenosha, we believed we’d removed the Event Page for violating our policies,” Facebook said in a statement. “Our investigation found that while we did remove the Kenosha Guard Page, the Event was removed by the organizer. We apologize for the error.”

Facebook’s failure to act raises serious questions about how the company moderates its platform.

A Facebook spokesperson told CNN Wednesday that the company was treating the shootings in Kenosha as a “mass murder” and was enforcing stricter rules on posts about it.

That policy, the spokesperson said, is being enforced by a team of specialists who study specific terminology and symbolism used by organizations that indicate potential violence.

The spokesperson acknowledged prior to the team of specialists handling the incident there may have been issues if someone reported the Kenosha Guard page. At least one user reported the page and no action was taken by Facebook’s regular content moderation team.

The spokesperson said as soon as the specialist team reviewed the page, it was shut down.

Update: This story was updated the week after it was initially published to reflect Facebook’s acknowledgement that it had not been behind the event’s removal.