MADISON, Wis. (AP) — Four people filed a federal lawsuit Wednesday demanding that Facebook prevent militias and hate groups from using the site, after a militia group used the platform to draw armed people to protests in Wisconsin last month that left two people dead.

Prosecutors have charged 17-year-old Kyle Rittenhouse with shooting and killing Joseph Rosenbaum and Anthony Huber during a protest in Kenosha on Aug. 25 over the police shooting of a Black man, Jacob Blake, two days earlier. A white officer shot Blake in the back seven times, leaving him paralyzed from the waist down.

Some of the protests turned violent, with demonstrators burning and looting buildings. Gov. Tony Evers had to call out the National Guard to gain control of the city.

According to the lawsuit, a militia group calling itself the Kenosha Guard put out a call on its Facebook page for armed people to guard property in the city, which sits along Lake Michigan between Milwaukee and Chicago. Among those who took up the call was Rittenhouse, who is from Antioch, Illinois, about 15 miles (24 kilometers) from Kenosha, according to the suit.

The plaintiffs, citing a Buzzfeed story, argue that Facebook received more than 400 complaints that the Kenosha Guard’s post but that the company’s content moderators conducted several reviews and decided the post didn’t violate Facebook’s anti-violence policies. The Kenosha Guard took down its call to arms the day after the shootings and Facebook took down the militia group’s entire page later that day, Buzzfeed reported.

The plaintiffs contend that Facebook was negligent for not removing the Kenosha Guard’s post. They’re seeking an injunction that would force the company to prohibit violent rhetoric, militias and hate groups from the site. They warn that such groups are still posting on Facebook and could use it to incite violence if President Donald Trump loses the Nov. 3 election but refuses to leave office. The plaintiffs also are seeking unspecified damages.

The plaintiffs include Hannah Gittings, who describes herself as Huber’s life partner, two people who say they were intimidated by the armed men at the Kenosha protests, and a journalist who came to the aid of one of the people who were shot.

“The planning and preparation exhibited in this post led to Plaintiffs and other protesters being terrorized, assaulted, harassed, and placed in so much fear when facing the business end of military grade assault rifles that they determined it was too dangerous to continue to protest,” the lawsuit said.

Facebook CEO Mark Zuckerberg has apologized for allowing the Kenosha Guard’s post, calling it an “operational mistake,” the lawsuit said. Facebook didn’t immediately reply to a Wednesday email seeking comment about the lawsuit.