Former BBC Newsnight presenter Paul Mason has explained how he came to be a member of a secret Facebook group in which antisemitic material was openly shared and discussed.

Mr Mason said "someone" had signed him up to the Palestine Live group, whose members also once included Jeremy Corbyn, while he was visiting Gaza in 2014.

Admitting he recognised the names of other "comrades" amongst the 3,200 members of the group, the former Channel 4 Economics Editor said those who had posted antisemitic material should be banned from Facebook and investigated over their comments.

Mr Mason claimed he had been unaware of the material being circulated on Palestine Live and that he did not always endorse groups he followed on Facebook.

Writing on the social media site, he said: “Apparently in 2014, while I was in Gaza someone signed me up to a FB group called Palestine Live which is now being accused of hosting antisemitic propaganda.

"I can see from a glance that a number of other comrades are members of it.

"I haven't fully read the report from a journalist called David Collier but I'm told there is evidence of some antisemitic postings.

"If so the people posting should be kicked off FB and investigated.

"For clarity I don't read, let alone endorse, stuff in the groups I follow - and would report any antisemitism and hate speech directed at me here.

"On Twitter I actively monitor numerous alt-right and antisemitic arseholes for journalism purposes but not here. I'll leave the group now."

Mr Mason posted his explanation yesterday, on the same day Mr Collier’s report was published.

Labour has launched an investigation into claims members of the party posted on Palestine Live.

Five individuals are said to have already been suspended.

Labour claimed Mr Corbyn was unaware of the antisemitic nature of some content on Palestine Live. He became a member prior to becoming leader but left the group after being elected to the top post in the party.

Jennifer Gerber, Labour Friends of Israel director, said: “That Jeremy Corbyn was a member of a Facebook group frequented by antisemites, Holocaust deniers and Israel-hating conspiracy theorists is both appalling and utterly unsurprising.

“We have long known about the kind of company that he keeps and this is simply further confirmation of a deeply disturbing pattern of behaviour.

“Mr Corbyn has repeatedly failed to apologise to the Jewish community and to recognise the hurt caused by his past actions and associations. Now would be a good time for him to do so.”

The secretary of Jewish Voice for Labour, Glyn Secker, was also a member of the Palestine Live Facebook group; yesterday JVL announced that he had been suspended from the Labour Party.

JVL referred to the suspension as “an absurd, politically-motivated attack on our secretary and our organisation.

“While antisemitism is monstrous – and, like all forms of racism, should be vigorously dealt with – false accusations of antisemitism are monstrous too.”