A white supremacist from Somerset who posted a series of vile and anti-Semitic comments about Luciana Berger MP has been found guilty of the racially-aggravated harassment after a three-day trial at the Old Bailey.

Joshua Bonehill-Paine, 24, who lives in Yeovil, heard the ‘guilty’ verdict read out just after 3pm on Wednesday – his birthday.

Bonehill-Paine became known to the Jewish community for organising an anti-Jewification rally in Golders Green in 2014. He pleaded not guilty this week, claiming his comments fell within the boundaries of free speech.

The jury at the Old Bailey heard how, while on bail, he wrote five blogs about Berger in the four months after fellow far-right activists Garron Helm was jailed in October 2014. He blamed the MP for Liverpool Wavertree for Helm’s sentencing, claiming she was an “evil money-grabber” and comparing her with a rodent.

In one article, Berger was described as being part of a “new line of Jewish MPs” ensuring “that white genocide happens without fail”. In another, Bonehill-Paine celebrated the 2,500 offensive tweets Berger received during “Operation Filthy Jew Bitch”. A month later, he was handed a suspended sentence.

Helm had earlier admitted sending an offensive tweet featuring a picture of Berger with a Holocaust-era Star of David on her head, under the hashtag #HitlerWasRight.

Prosecutor Philip Stott said “the ideology which so stirred Mr Bonehill-Paine is one of fierce anti-Semitism” and that he had demonstrated “hostility based on her membership or presumed membership of a particular racial group, namely Jews”.

Reacting to the verdict, the Community Security Trust said: “We applaud [Berger’s] courage in reporting his abuse and giving evidence against him. This conviction sends a strong signal that online hate will be prosecuted.”

Stephen Silverman from Campaign Against Antisemitism said: “He abused her with many well-worn anti-Semitic tropes, including the Jew as Christ killer, the Jew as sexually deviant, the Jew as vermin and the Jew as a grasping money-grabber. This verdict should stand as a warning.”