Sadiq Khan’s office has expressed concern after false and racially oriented social media messages about London’s ultra-low emission zone (Ulez) were viewed hundreds of thousands of times without being taken down. The concern over the tweets, which falsely claim the London mayor plans to exempt Muslims and other “minority religions” from the charge, came after analysis that indicated there could be a paid-for campaign using fake accounts on X, formerly known as Twitter, to amplify anti-Ulez sentiment. Khan’s plan to expand the zone, which charges drivers of the most heavily polluting vehicles £12.50 a day, to outer London has become politically controversial, especially since the Conservatives narrowly won the Uxbridge byelection with a campaign heavily focused on opposing the plan. Ulez has increasingly become a focus for social media abuse of the Labour mayor, who has been targeted by an estimated 300,000 pieces of openly racist or racially oriented abuse since he assumed office in 2016. The latest incarnation, sent by a series of rightwing accounts, features a faked newspaper article about Khan’s supposed plan for a religious exemption. The mocked-up article says Khan had announced at a press conference that people travelling for a medical emergency or “prayer for the minority religions” would not have to pay the charge even if their car was heavily polluting. Khan is Muslim, with Islam identified as one of the faiths supposedly exempt. “Which religion do you think Seditious Khant has left out of his exemptions from ULEZ?” one tweet viewed over 200,000 times said. Separate analysis by Valent Projects, a social media disinformation consultancy, identified around 3,700 seemingly fake Twitter accounts used to “amplify” anti-Ulez tweets from genuine accounts, in an apparent attempt to make the opposition seem more significant. Doing this on such a scale would cost around £44,000, the company estimated, saying that there was no sign of who might have paid for this, or any indication that genuine anti-Ulez tweeters knew their messages were being spread this way. A source close to Khan said the mayor accepted that some people had valid questions and concerns about the expansion. They said: “This research seems to show that well-funded and sophisticated campaigns are being run online spreading misinformation and stoking fears about the policy. “It’s up to social media companies and also politicians to redouble our efforts to tackle misinformation online – whether around cleaning up our air, vaccines rollout, or other areas of public policy.” A study conducted by the Greater London authority last month showed that Khan, who is seeking a third term as mayor next May, had received nearly 11,000 racist social media messages since the start of the year, with a particular rise in those referencing Ulez. Khan’s Conservative opponent in the mayoral race, Susan Hall, has said she would immediately reverse the expansion, which is due to start on the 29 August, if she was elected. The zone, instigated by Boris Johnson when he was London mayor, initially covered just central London, but was then expanded as far as the north and south circular roads.