Facebook on Tuesday announced a ban on all accounts linked to the QAnon conspiracy group, as the social network tries to clamp down on misinformation ahead of the heated US presidential election.

The move against QAnon at Facebook and its image-sharing platform Instagram comes as the online giant tries to avoid being used to deceive or confuse voters, as was the case during the 2016 election that put US President Donald Trump in the White House.

“We will remove any Facebook pages, groups and Instagram accounts representing QAnon, even if they contain no violent content,” the internet titan said in a blog post.

From an anonymous 2017 posting claiming bizarre child exploitation and political plots, the headless and bodiless movement has earned a place in Trump's Twitter stream.

The FBI last year said in a report that QAnon was one of several movements that could drive “both groups and individual extremists to carry out criminal or violent acts”.

The ban on QAnon accounts steps up Facebook's efforts to clamp down on misinformation campaigns sometimes endorsed by Trump, weeks ahead of the November 3 presidential election.

“Facebook's decision to ban QAnon from all its platforms is a much needed, if belated, step to purge dangerous conspiracy theories from the platform,” said Anti-Defamation League chief executive Jonathan Greenblatt.

“We hope that this is a sincere effort to purge hate and antisemitism from their platform, and not another knee-jerk response to pressure from members of Congress and the public.”

The moves made across Facebook and Instagram were against accounts tied to “offline anarchist groups that support violent acts amidst protests, US-based militia organisations and QAnon,” according to the blog post.

The leading social network recently prohibited ads that praise, support or represent militarised social movements and QAnon.

Facebook in August removed hundreds of groups tied to QAnon and imposed restrictions on nearly 2,000 more as part of a crackdown on stoking violence.

Critics have charged that inflammatory content from QAnon was spreading on Facebook despite the platform's proclaimed effort to contain it.

Stoking flames

Facebook said it tightened its prohibition on QAnon after noticing that, despite taking down posts directly promoting violence, QAnon supporter messages adapted to avoid restrictions.

For example, QAnon used the platform to claim deadly wildfires raging on the West Coast were started by certain groups, which diverted attention of police and firefighters.

“QAnon messaging changes very quickly and we see networks of supporters build an audience with one message and then quickly pivot to another,” Facebook said.

The social network already bans content calling for violence and organisations that proclaim violent missions. The increasingly visible and vocal followers of QAnon promote a bewildering blend of unsubstantiated conspiracy theories.

Once on the fringes of the internet and focused on US politics, the movement has seen sharp growth on mainstream social media platforms this year.

The movement centered on the unsubstantiated belief that the world is run by a cabal of Satan-worshippers has extended that this year to allege, without proof, that the coronavirus is a conspiracy by that group to control people using vaccines and 5G.

Social media platforms including Facebook, Twitter, TikTok and YouTube have ramped up surveillance for QAnon content, as adherents attempt to bypass the new filters.