A research project analysing Twitter activity surrounding the murder of MP Jo Cox earlier this year found that more than 50,000 abusive tweets were sent by at least 25,000 people in celebration of her death. The report due to be published on Monday will argue that social media companies take further action against online hate speech.

The report found that the most commonly used words in the tweets included "hero", "patriot", "white power", "rapist" and "traitor" according to The Guardian. The findings will back the views of campaigners who have claimed events such as June's Brexit vote have emboldened or legitimised the far-right views of many who had previously been under the radar.

MP for Batley and Spen, Cox, was killed by Thomas Mair who was last week tried as a terrorist for her murder on the grounds that the act was "motivated by hate" according to Sue Hemming, head of special crime and counter-terrorism at the Crown Prosecution Service.

It was found, during the trial, that Mair kept a collection of Nazi and far-right materials in his home as well as visiting far-right websites. Mair was found guilty of Cox's murder on 16 June, just a week before the referendum on the UK's membership of the EU, and sentenced to prison for the rest of his life.

Speaking after Mair's verdict was returned, Nick Lowles, chief executive of Hope not Hate, said: "In targeting a British MP, Mair was following a growing list of British Nazi terrorists who believe that they are at war with the system.

"This ideology, which sees the state – and in particular liberal politicians – as more of a target than minorities, became dominant among UK Nazis in the 1990s and remains a strong pillar of their thinking today.

"While Thomas Mair pulled the trigger, neo-Nazi propagandists must share some responsibility for fuelling and directing the hatred and violence inside him."

Following Mair's trial, authorities also warned of a rise in far-right groups. Neil Basu, senior national co-ordinator for counter-terrorism policing, said there had recently been "indications that the threat from the extreme right wing could be increasing and we are alive to this".

On the report carried out by Dr Imran Awan of Birmingham University and Dr Irene Zempi of Nottingham Trent University, Lowles referred to the increasing use of social media sites for hate speech and said: "It is time for the authorities to take greater note of these ideologues of hate, and time too for social media companies – and Twitter in particular – to up their game when it comes to providing a safe platform for expression. Free speech does not equal hate speech, which can have very real consequences and impact in communities in the UK."

Jo Cox
The research found over 50,000 tweets were sent in celebration of the murder of Jo Cox by Thomas MairGetty Images