On Wednesday afternoon, he was found guilty of racially aggravated harassment. The Old Bailey jury deliberated for just 75 minutes before reaching its verdict.

Bonehill-Paine, 24, had posted five “hateful and insulting” articles about Ms Berger in which he branded her “a rodent”, a “money grabber” and “evil”. He was expected to be sentenced on Thursday.

The jury was not told that Bonehill-Paine had been sentenced to three years and four months in prison in December 2015 for inciting racial hatred against Jews by organising a neo-Nazi march in Golders Green. A flyer featuring a picture of Auschwitz said the planned rally would be “a gas”.

Welcoming the guilty verdict, the Community Security Trust applauded the MP’s courage “in reporting his abuse and giving evidence against him.

“This conviction sends a strong signal that online hate will be prosecuted when it breaks the law. We hope it sends a signal to the police and CPS to pursue others who use the internet to spread vile hatred.”

Bonehill-Paine, who remained silent during the three-day trial, waved to supporters, including known far-right sympathisers, in the public gallery. As he was led away, he made a victory sign.

In his first email of July 6, he wrote: “Justice for Joshua Bonehill-Paine will be sweet, he has friends everywhere. Watch your back Jewish scum, regards your friend the Nazi.”

He followed it up two days later with: “You will get it like Jo Cox did, you better watch your back Jewish scum”.

Ms Berger told the court she “felt sick” on seeing antisemitic blogs describing her as “a rodent” and a “money grabber”.

“It’s attacking me for my faith or religion and not something I have said or done for my constituents,” the Liverpool Wavertree MP said, adding that she had feared for her safety since being elected.

Hate messages had escalated following the imprisonment of far-right activist Garron Helm in October 2014.

Helm was jailed for four weeks after pleading guilty to sending a malicious communication by tweeting a picture of Ms Berger with a Star of David superimposed on her forehead, accompanied by the words “Hitler was right”.

The prosecution said Ms Berger received in excess of 2,500 messages on Twitter as part of a “Filthy Jewish Bitch” campaign. “The police were in constant contact with me,” Ms Berger said. “I had police patrolling outside my home and office.”

Bonehill-Paine, of Yeovil, Somerset, was arrested on February 13 last year.

On being charged, he allegedly said: “I am really pleased. This gives me an opportunity to be found not guilty, hopefully at a full Crown Court trial, with the media that will bring.”

Prosecutor Philip Stott told jurors: “Both the language and the imagery deployed in these articles are strongly offensive. You might think the message they convey is even more so, that Ms Berger is, through her membership of the Jewish faith and community, ‘filthy’, ‘money-grabbing’ and a ‘dominatrix’, ‘evil’ — in short, to be detested.”

The prosecutor highlighted more examples of Bonehill-Paine’s “passionate hatred of the Jewish community” in YouTube rants from the time.