Aaron Bastani, the co-founder of left-wing Novara Media news site said the revelation was “highly significant”, accusing Gnasher Jew of “smearing” Labour members.
He tweeted: “This appalling account has been making the most disgraceful assertions about Labour members, often boosted by Corbyn-sceptic MPs.
“It turns out they are a Tory activist. Some things are unacceptable in politics. This is one of them.”
Ms Phillips defended her actions, saying she "reports and seek to exclude racists from my party".
She said: "Someone on Twitter set me evidence of someone (alleged from a Lab CLP) saying something antisemetic.
"I replied saying I'd report it to party as (Labour's general secretary Jennie Formby) has told Lab MPs to do."
But the JC understands that after carrying out an investigation into Mr Humphries, Labour found he was responsible for a stream of other antisemitic postings.
In one, he contacted Jewish MP Luciana Berger and demanded that she made a statement after writing:"Do you agree in killing all the PALISTINIONS? (sic)"
He added: "It's a simple answer - yes or no? If you don't reply I will take this as a yes...you agree with Palistine genocide by the Israeli government."
Mr Humphries then wrote of Ms Berger on the We Love Jeremy Corbyn Facebook page: "If she doesn't reply I might just go to the media."
In other messages Mr Humphries shared antisemitic images and statements alleging Rothschild world domination and also attempted to defend the actions of Syrian President Bashar al-Assad.
It is understood that Mr Humphries was informed he had been expelled by Labour during the past few weeks.
On Wednesday, he said: "I have just been expelled for writing similar posts which other people wrote."
