The brother of former Labour leader Jeremy Corbyn was one of 19 protesters arrested during a protest against the coronavirus lockdown.
About 50 people defied social distancing to gather close together at Speakers' Corner in Hyde Park, west London, holding placards with slogans like "anti-vax deserves a voice" and "freedom over fear".
Dozens of police officers, including some on horseback, patrolled the protest, issuing 10 on-the-spot fines and making 19 arrests.
Piers Corbyn was taken away after showing up with a megaphone and proclaiming 5G and the coronavirus pandemic were linked, calling it a "pack of lies to brainwash you and keep you in order".
There is no evidence to link 5G and Covid-19 and scientists fear that a rise in measles among children can be attributed in part to unfounded fears about vaccines.
He was taken away after declining to leave when asked by a police officer and refusing to give his details when asked.
A flyer advertising the protest called for "no to mandatory vaccines, no to the new normal, and no to the unlawful lockdown".
David Samson, 50, who said he works in finance, said he went because "I never thought I’d see in my generation the suppressing of civil rights" over a "fake virus".
"This is nothing compared to what’s coming," he said.
There was a large round of boos whenever protesters were arrested, and repeated shouts of "jail Bill Gates".
Another demonstrator, 62-year-old Catharine Harvey, said she was defying the rules to highlight the “devastation this lockdown has caused”.
The shop owner said: “Developing countries will have no trade, no tourism. I have had to close my shop on Columbia Road flower market.
“The effects of the lockdown are far, far worse than the virus – mental health, domestic violence, shops are closed, theatres, cinemas, restaurants. It’s unnecessary.”
Deputy Assistant Commissioner Laurence Taylor said: “With the easing of restrictions we fully expected open spaces to be busy this weekend.
“It was disappointing that a relatively small group in Hyde Park came together to protest the regulations in clear breach of the guidance, putting themselves and others at risk of infection.
“Officers once again took a measured approach and tried to engage the group to disperse.
“They clearly had no intention of doing so, and so it did result in 19 people being arrested, and a further 10 being issued with a fixed-penalty notice.”
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