An officer of the pro-Jeremy Corbyn, fringe Jewish Voice for Labour group has claimed a prominent researcher into the party's antisemitism was being fed his information by MI5.

Mike Cushman, JVL's membership officer, told an audience revelations of antisemitism from Labour members on social media – which he referred to as a “smear campaign” - require “serious, heavyweight artificial intelligence”.

He said he had come to the conclusion it was the "British security services", not Mossad as he suspected, that was behind "this mining that’s fed to people" such as David Collier, a researcher who has published several landmark reports on Labour antisemitism.

Mr Cushman was speaking at an event during Labour conference in Brighton in September.

The event, which was launching Bad News for Labour, a book that claims the idea of Labour antisemitism is exaggerated by a hostile media, had to be moved after the local Waterstones backed out of hosting after complaints. 

A recording of the event published on the Harry’s Place website reveals Mr Cushman said: “I don’t know about anybody else but I can’t find a Twitter post I did a month ago, let alone what someone else did six years ago.”

He said he had always “naively assumed that the heavyweight IT behind this was coming from Tel Aviv from Mossad because that’s the sort of thing they do.”

But having read an article on a website called “OffGuardian” – which says it was started by five people who had “all been censored on and/or banned from the Guardian’s ‘Comment is Free’ sections” and claims to “provide a home for the comment – & the facts – you no longer find in the MSM” – Mr Cushman said he had come to another conclusion.

“Reading an article in the Off Guardian last week about the way The Guardian has been subverted and taken away from doing any investigative journalism by direct intervention by MI5 makes me begin to suspect that this mining that’s fed to people like David Collier is actually coming from the British security services, in an effort to stop us from having a socialist government in this country because this is what MI5’s job has been for many, many years”.

After Mr Cushman spoke, his JVL colleague, Naomi Wimborne-Idrissi, the group’s media officer, praised his “excellent point about the security services.”

Mr Collier responded by tweeting to “MI5 and Mossad”, saying, “me old mates Cushers and Idrissi from Jewish Voice for Labour tell me that you owe me bags of money.

“Can I have it please (if there's a problem - revert to them - they seem pretty certain).”