Tommy Robinson has been arrested a day after organising a major demonstration in central London, according to his X account. Thousands of people marched in the city on Saturday as part of an event organised by Robinson, whose real name is Stephen Yaxley-Lennon, while many others took part in a counterprotest. A post on Robinson’s X account on Sunday said: “We can confirm that Tommy Robinson has been detained by police using powers afforded to them under the Terrorism Act 2000.” Kent police said on Sunday night that a man, 41, had been detained at the Channel tunnel in Folkestone under schedule 7 of the Terrorism Act, which allows police to stop, examine and search passengers at ports, airports and international rail terminals. He was subsequently arrested “for frustration of a schedule 7 examination”, the force said, and was later released on bail while inquiries continue. The anti-extremism campaign group Hope Not Hate said on Saturday that Robinson “could face jail” after allegedly screening a documentary against high court orders at the demonstration. The film, Silenced, repeats false claims he made about a Syrian refugee that led to him losing a libel case in 2021. Robinson is due to appear at a high court hearing on Monday accused of contempt of court for making the documentary. While the circumstances of any arrest remained unclear, supporters of the far-right activist gathered outside Downing Street on Sunday after an impromptu protest was called for 4pm. The Met said it was aware of posts encouraging people to protest in London and that any such activity must be lawful. “We will deploy officers as required to prevent serious disruption or disorder and to deal with any incidents,” it added. The Reform UK party MP Rupert Lowe, responding to the reported arrest, tweeted: “Is this action proportionate and in line with how the streets of London have recently been policed? More details are urgently required.” Before the release of further details by the authorities, others including the X owner, Elon Musk, tweeted questions on social media. The Met had said in advance of Saturday’s protests that about 1,000 officers were being deployed across the capital to “keep the peace” and ensure the two groups of protesters were kept apart. At least eight people were arrested and several emergency workers were assaulted, according to the force.