Labour has expelled the activist who criticised Jewish MP Ruth Smeeth at the launch of a report on antisemitism in the party.
Marc Wadsworth was found guilty of having breached party rules after accusing Ms Smeeth of working "hand-in-hand" with right-wing newspapers.
He was expelled by the party's National Constitution Committee (NCC), which deals with disciplinary matters. It marks the culmination of an almost two-year process following the incident in June 2016.
A Labour spokesperson said: “The National Constitutional Committee (NCC) of the Labour Party has found that two charges of a breach of the Labour Party's rule 2.1.8 by Marc Wadsworth have been proven.
“The NCC consequently determined that the sanction for this breach of Labour Party rules will be expulsion from membership.”
Stoke-on-Trent North MP Ms Smeeth said: "Abuse, bullying and intimidation have no place in our movement, as today's announcement has proven.
"I hope that this decision represents the first step towards a return to the values of decency and respect throughout the Labour Party."
Mr Wadsworth, who runs Momentum Black Connexions, had accused the MP of "working hand in hand" with The Daily Telegraph during a tirade at the launch of the Chakrabarti report in 2016.
Dozens of Labour MPs had marched in support of Jewish colleague Ms Smeeth as she prepared to give evidence at Mr Wadsworth's disciplinary hearing this week.
Ahead of the hearing, Mr Wadsworth told reporters: "I'm confident, as I'm not guilty. Based on the facts, this hearing, if it's fair, I will be exonerated.
"I'm totally and utterly opposed to antisemitism, to all forms of bigotry, including anti-black racism and Islamophobia."
The decision on Mr Wadsworth came as Ken Livingstone - who is currently suspended from Labour over remarks linking Adolf Hitler and Zionism - said rows over antisemitism in the party are a "complete diversion".
Mr Livingstone told LBC: "I'm not discussing antisemitism until after the election is all out the way because it is a complete diversion.
"We had this last year in the run-up to the local elections then. We had it two years ago in the run-up to the election of Sadiq Khan.
"It didn't damage us at the last two local elections but it is a complete diversion.
"Every Labour MP should just be focused now on getting out the Labour vote and winning council seats."
Mr Livingstone avoided expulsion in April at a disciplinary hearing into his conduct but was suspended for a further year.
One of the flashpoints at a failed meeting between Jeremy Corbyn and Jewish leaders over antisemitism in Labour was the party's handling of the former MP's case.
The attempt to smooth relations with the community backfired for the Labour leader as leaders of the Board of Deputies of British Jews and Jewish Leadership Council (JLC) accused him of failing to back his words with action.
But Unite union leader Len McCluskey voiced "disgust" at backbench Labour critics of Mr Corbyn, raising the prospect that those who have attacked him over issues such as antisemitism could face mandatory reselection.
Gillian Merron, chief executive of the Board of Deputies of British Jews and a former Labour MP, said the meeting with Mr Corbyn "did not go as well as hoped" but there had been "positive movement" in recent days.
Writing on the Labour List website, she said it was concerning when Labour MPs "show support to people who have been barred for antisemitism, as this suggests that what they are accused of is a small matter".
In a message to Mr Corbyn, she said: "If he is to show his seriousness about tackling this problem, Jeremy cannot continue to engage with anyone, Jewish or not, who seeks to obstruct efforts to tackle the problem."
Labour said 90 current cases of antisemitism are under investigation, making up around 0.02% of Labour's membership of around 500,000.
Over the past three years, a total of 300 complaints have been made over antisemitism, around half of which had led to people being expelled from or leaving the party.
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