Furious Labour MPs have called upon the party to re-open an investigation into alleged antisemitism by two students at Oxford University.
At a meeting of the parliamentary Labour party on Monday night, MPs Ian Austin, Ruth Smeeth and John Mann all hit out at the NEC's ruling.
Last week the JC revealed how the party's national executive committee had decided that no action was being taken against the pair, both members of the Oxford University Labour Club.
This was despite party bosses ruling that the students, who were both supporters of leader Jeremy Corbyn, should be given a warning for their behaviour.
Speaking at Monday's PLP meeting Mr Austin said: "Last week's decision resulted in fury in the Jewish community and has been criticised by the Chief Rabbi, the Board of Deputies, the Jewish Labour Movement and the all-party group on antisemitism.
"There was a poll last year that showed that the Labour party now has the support of 8% of the Jewish community - a party that can only rely on the support of 8% of any community doesn't deserve the support of anybody else. This has to be looked at again."
Mr Mann, who is chair of the all-party group, said: "This decision brought shame on the Labour party."
Labour peer Baroness Royall - whose own probe into the affair found there had been incidents of antisemitism by members of the club - had openly condemned the NEC's decision to drop the investigation.
Labour general secretary Iain McNicol said MPs concerned about the decision should take it up with NEC members.
Labour peer Baroness Royall, who had previously investigated the Jew-hate allegations, said: "I am deeply disappointed by the outcome and fear it will further harm relations between the Jewish community and our party by confirming a widely held view that we do not take antisemitism seriously.
"It also doesn't bode well for the outcome of the ongoing inquiry into Ken Livingstone's behaviour."
Jeremy Newmark, national chair of the Jewish Labour Movement, added: “The decision rides roughshod over concerns and experiences of our student members.
“They have confronted the impact of antisemitism at OULC first hand. They do not feel comfortable attending meetings of their own Labour club.
“This has been looked at by three inquiries and one investigation. They have not heard from the party for nearly a year – even to inform them of this decision.
“It is many months since Chakrabarti recommended an over haul of the complaints and investigations process but seemingly nothing has changed.”
Following the claims last February, Baroness Royall, a Labour peer, conducted an internal inquiry into claims of antisemitism at the club.
She received 300 pages of evidence from more than 40 OULC members and interviewed eight group members.