The UK’s most prominent politicians were subjected to a deluge of abuse on X during the general election period, one of the most comprehensive studies of online abuse in politics has found.

Five politicians – Rishi Sunak, Keir Starmer, Diane Abbott, Suella Braverman and Sadiq Khan – were, between them, sent more than 85,000 clearly abusive messages between 1 May and 30 July, according to the findings from researchers at the University of Sheffield.

The researchers initially looked at abusive posts towards 14 politicians in the spring, before narrowing the focus to the five most frerquently targeted. They said the volume of abuse they recorded was likely to underestimate the reality, as not all of it was caught by the study.

More than 6% of all replies to Sunak, Starmer, Abbott, Braverman and Khan between May and July were clearly abusive. In most cases, these politicians would receive their first abusive reply within one to two minutes of publishing a post on X, which the researchers said was “extraordinarily fast”.

The study monitored a range of abusive messages ranging from “milder” posts branding politicians liars to more severe abuse including personal attacks and racist and sexist insults.

More than 8,000 messages directed at the five politicians contained the word “liar”, 3,000 “cunt”, and 2,000 “criminal”. Nearly 20% of the abuse was explicitly sexist, misogynistic or sexually explicit.

In examples highlighted by the researchers, Sunak, Khan, Abbott and Braverman were all subjected to racist abuse, including slurs such as being told to “go back to where they came from”.

There was a clear increase in the overall volume of abuse throughout June while the election campaign was in full swing. Notable spikes occurred in the days leading up to polling day on 4 July, and in early June after the first televised debate between Sunak and Starmer and the 80th anniversary of D-day commemorations.

Khan and Sunak received the most abuse of the politicians monitored. Overall, Labour and Conservative politicians were targeted more or less equally. The three main topics seen in abusive messages were democracy, foreign affairs, and borders and immigration.

“Our analysis shows very clearly the ways in which people vent their anger at world events, such as the Israel-Hamas war, by lashing out at politicians as a way of finding someone to blame. We saw the same thing during the pandemic and events such as terrorist attacks,” the Sheffield researchers said.

“The sheer number and strength of racist comments towards politicians is terrifying in a supposedly tolerant country like the UK. While any politician needs to have a thick skin, those from racial minorities really need a suit of armour to survive the vicious racial attacks from those who do not support their views.”

There were big spikes in abuse against Abbott in March, when the Guardian revealed comments made by the Conservatives’ biggest donor, Frank Hester, and in June when there was a row over whether she could stand for re-election. The Labour MP for Hackney North and Stoke Newington, London, is a particular target for sexist and racist abuse and personal insults about her appearance and intelligence.

Abbott told the Guardian: “I have been on the end of huge amounts of abuse on Twitter [X]. At the time of the 2017 general election an Amnesty investigation found I got more online abuse than all the other women MPs put together.

“One way of cutting back on online abuse would be – although tweeters and users of online platforms could post under a pseudonym – [if] Twitter and other online carriers would retain their real name and address so they could be easily investigated.”

The University of Sheffield researchers were limited in their ability to track abuse against all politicians on X because after it was bought by Elon Musk, the platform revoked free access to its application programming interface (API). In 2023 Musk instigated a paid regime instead where equivalent data access starts at $42,000 (£33,000) a month.

While EU researchers qualify for free data access on X because of the provisions within the EU Digital Services Act, there is no equivalent clause in the Online Safety Act to benefit UK researchers.