Facebook is “working to restore” a number of groups that were erroneously removed or affected by “sabotage,” according to the company. A spokesperson told The Verge the social network “removed several groups from Facebook after detecting content that violated our policies.” After investigation, it discovered content had been “posted to sabotage legitimate, non-violating groups.” Facebook is working to restore any groups affected and to “prevent this from happening again.”

The situation allegedly began on May 13th. A popular meme account on Facebook known as Crossovers Nobody Asked For (CNAF), which boasts more than 500,000 members, was suddenly shut down. The group’s administrators tried to corral its users into a new group, “Crossovers Nobody Asked For ‘Season 2,’” but that got shut down just one day later.

Know Your Meme reported that members of CNAF were able to track down a screenshots of a group known as Indonesian Reporting Commission (IReC) celebrating CNAF’s page being taken down, leading to suspicions among those involved that IReC was behind the attacks. Facebook would not confirm if the Indonesian Reporting Commission, which gets groups and pages suspended through posting questionable content and mass reporting it, was behind the false flags.

The news spread quickly, and caused thousands of popular Facebook pages to switch from “private” to “secret” mode in order to prevent themselves from being shut down. While closed Facebook groups require moderators to approve someone’s request to join, secret groups are virtually undetectable. A group moderator has to personally invite someone to join; you can’t just search for it.

The attack on two high-profile groups, though seemingly isolated, has been felt by a substantial number of Facebook users. People complained on Facebook and Twitter about waking up to an array of notifications from various groups they belong to recognizing the status change from “private” to “secret.” Others have spoken out about their own groups asking members to be patient as they lay low. Facebook users have started calling it “The Great Zuccening of 2019” or in some cases “Groupocalypse.”

The incident is concentrated largely among a network of popular meme pages and groups. But the fear of suspensions or bans at the hand of Facebook’s algorithmically-driven reporting system, supposedly underpinned by its ongoing AI efforts, underlines the vulernability of the social network’s s moderation approach.

Facebook has long had issues with overseeing user-uploaded content. Those issues extend to everything from its heavy-handed stance on nudity, which gets popular artwork and famous photographs erroneously pulled down, to its failure to recognize when immediately viral content, like the Christchurch shooting, is in fact a graphic video violating multiple rules that needs to be uniformly blocked. Though this is a relatively anodyne situation involving meme pages, the widespread panic among some of the most active groups and pages on the platform shows how little faith users have in the company’s ability to foresee these issues and prevent fallout, rather than react after the fact.

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One group dedicated to BoJack Horseman shitposts posted a link to the Know Your Meme explainer on the situation, notifying members that they were “doing the hide from the mean jerks reporting groups thing.” Frank Scarsella, the group’s admin, told The Verge he first noticed what was happening after “several of the pages I am just a member of started throwing up these notifications.

“Some of those groups I’m in were much more likely to be targets, honestly, but I immediately let my team know so we could discuss our own moves,” Scarsella said.

There was a conversation amongst Scarsella and his moderators when the notification flags from other groups started picking up, and they debated about whether they should close i their own group in response. Most of the team wanted to air on the side of caution, Scarsella said, adding “the comfort of the group is always paramount to me, so for the sake of reducing fear, I sided with closing off the group.”

“For the sake of reducing fear, I sided with closing off the group.”

“Better safe than sorry,” as Scarsella said, seems to be the reason for the panic across Facebook. Know Your Meme’s managing editor Don Caldwell thinks that after users started waking up to notifications of group status changes, and after stories started spreading about a suspicious Facebook group reporting a series of popular pages with hundreds of thousands of members, “people got pretty spooked.”

“All the spam notifications that went out to all those members, and rumors that started spreading, getting posted in those groups — it becomes a big thing,” Caldwell said.

There’s an issue with changing a group from private to secret, though. If the status isn’t changed within 24 hours, the group has to remain secret for another 28 days. This isn’t a big deal for tinier groups built on a close-knit community — something that Facebook has tried to promote recently — but it does matter for pages who want to build a member base. Caldwell couldn’t predict whether groups will remain secret for some time or start to revert back, but people are spooked enough that every precaution is being taken. Even Scarsella, who doesn’t think it’s likely “someone in the group will go on a mass reporting spree,” is worried about possible repercussions.

“The group is a very important community to so many people, myself included,” Scarsella said. “There is always worry that the platform could remove that community. I’d say [we’re] mildly worried because it seems unlikely, but would have heavy repercussions for us.”

Some of the groups removed in the original flood of mass reporting, including Crossovers Nobody Asked For, have since returned to Facebook.