Facebook on Wednesday removed accounts of a teenager accused of a deadly shooting spree during protests in the US city of Kenosha, along with pages of a local militia.

The 17-year-old was arrested on murder charges after two people were shot dead and a third wounded during anti-police protests in the Wisconsin city Tuesday night.

"We've designated this shooting as a mass murder and have removed the shooter's accounts from Facebook and Instagram," the internet titan said in response to an AFP inquiry.

Facebook added that it also removed a Kenosha Guard page and an event page posted by the militia group for violating a recently instituted ban on groups that celebrate violent acts or suggest people seek armed conflict.

"At this time, we have not found evidence on Facebook that suggests the shooter followed the Kenosha Guard Page or that he was invited on the Event Page they organized," the social network said.

"However, the Kenosha Guard Page and their Event Page violated our new policy addressing militia organizations and have been removed on that basis."

Facebook planned to remove any content supporting or praising the violence or those behind it.

The tech firm is also blocking accounts from being created in the accused killer's name.

Protesters run as police shoot teargas in an effort to disperse demonstrations against the shooting of Jacob Blake in Kenosha, Wisconsin on August 25, 2020, with Facebook saying it has removed accounts linked to the violence
Protesters run as police shoot teargas in an effort to disperse demonstrations against the shooting of Jacob Blake in Kenosha, Wisconsin on August 25, 2020, with Facebook saying it has removed accounts linked to the violence AFP / KAMIL KRZACZYNSKI

Outrage erupted after Kenosha police shot African American Jacob Blake in his back point-blank multiple times in the Midwestern city last Sunday.

Protesters have demonstrated every night since, with the rallies descending in to violence later at night.

Videos taken overnight Tuesday show a vigilante shooting at protesters with an assault rifle and apparently hitting two who tried to stop him.

The man then walks down the street freely, gun slung across his chest, while protesters scatter and police vehicles drive past him.

Police in Antioch, Illinois, about 20 miles (32 kilometers) southwest of Kenosha later announced that they arrested a 17-year-old wanted in Kenosha for murder.

Facebook last week said it had removed hundreds of groups tied to the far-right QAnon conspiracy theory and imposed restrictions on nearly 2,000 more as part of a crackdown on stoking violence.

The moves, which were made across both Facebook and Instagram, were against accounts tied to "offline anarchist groups that support violent acts amidst protests, US-based militia organizations and QAnon," the social media platform said in a blog post.

The platform has seen growth in movements that celebrate violence or weapons and hint at using them but stop short of directly organizing any action, Facebook said.