Two founders of Extinction Rebellion were caught up in a race storm yesterday after virulently anti-Semitic messages were posted on a Facebook page linked to the movement.

The posts were among several examples of extremist material and sinister conspiracy theories on the page run by Left-winger Gail Bradbrook, one of the people behind XR.

When a supporter asked why fake news accusing the British Government of trying to poison former KGB man Sergei Skripal and his daughter was on the page, Ms Bradbrook replied: 'People are free to post information in the general subject area.'

The posts were among several examples of extremist material and sinister conspiracy theories on the page run by Left-winger Gail Bradbrook (pictured), one of the people behind XR

The offensive posts included:

A link to a blogpost quoting from an infamous fake 19th Century Russian anti-Semitic tract Protocols of the Elders of Zion.

A meme of Guy Fawkes carrying a barrel of gunpowder outside Parliament, captioned 'Plan B', adding: 'Waving banners and asking nicely for them to stop is not working.'

A post expressing solidarity for Chris Williamson just a day after the Labour MP was first suspended by his party for alleged anti-Semitism.

A vile meme comparing Iain Duncan Smith to Adolf Hitler over the former Work and Pensions Secretary's treatment of the disabled.

Mother of two and practising Pagan Ms Bradbrook, 47, is an administrator of the Facebook group Compassionate Revolutionaries.

She is also a director of Compassionate Revolution, a non-profit company which holds the XR bank account.

When a supporter asked why fake news accusing the British Government of trying to poison former KGB man Sergei Skripal and his daughter was on the page, Ms Bradbrook (pictured in a rally in Bristol on July 15) replied: 'People are free to post information in the general subject area'

Mother of two and practising Pagan Ms Bradbrook (pictured on Waterloo Bridge in April), 47, is an administrator of the Facebook group Compassionate Revolutionaries

Her partner Simon Bramwell, a co-founder of XR, is an administrator of the Facebook group.

The news came as XR blocked roads in several major cities last week.

Activists were forced to apologise after blocking the M32 in Bristol and preventing a man from reaching his dying father in hospital.

Activists were forced to apologise after blocking the M32 in Bristol (pictured) and preventing a man from reaching his dying father in hospital

Ms Bradbrook said: 'I'm horrified to have been alerted to anti-Semitism showing up in a Facebook group I'm associated with. As a busy mum I don't have time to monitor everything. As soon as I heard I immediately closed the page to further posts.'

In a report by the Policy Exchange think-tank, called Extremism Rebellion, anti-terror expert Richard Walton said the eco-friendly image of XR concealed an anarchic organisation whose leaders planned to overthrow capitalism – and even parliamentary democracy itself – by illegal means.

Ms Bradbrook said: 'We are absolutely non-violent in responding to profound existential threat.'