Facebook Inc chief executive officer Mark Zuckerberg took responsibility and faulted his company for not removing the page and event for a militia group before two people were killed at a protest in Kenosha, saying it was "largely an operational mistake".
The page and event listing violated Facebook's policies and should have been removed after numerous complaints were received concerning the group's violent nature, Mr Zuckerberg said in a video to employees that he posted publicly on his Facebook profile.
The social media company removed the page for "Kenosha Guard', and an event listing for "Armed Citizens to Protect Our Lives and Property" a day after the shooting on Tuesday (Aug 25).
Two people were killed during protests in Kenosha that broke out in reaction to the police shooting of a black man earlier this week.
"The contractors and reviewers who the initial complaints were funnelled to basically didn't pick this up," Mr Zuckerberg said.
"And on second review, doing it more sensitively, the team that's responsible for dangerous organizations recognised that this violated the policies and we took it down."
Mr Zuckerberg said there was no evidence the person charged with the shooting followed the Kenosha Guard page, but added that the company will continue to evolve its policies for identifying potentially dangerous organizations.