Extinction Rebellion activists from Norfolk were among those staging sit-down protests blocking London streets to call for an end to investment in fossil fuels.
Norwich XR group and others from Norfolk were among thousands of demonstrators that gathered at Speakers' Corner at Hyde Park on Saturday before moving to Oxford Street and Regent Street, where they sat in the road and blocked traffic.
They chanted "save our planet" and "whose streets, our streets" and waved multicoloured flags and banners that read "I am here for nature and children", "navel gazing into disaster" and "life on Earth is dying".
The crowd later headed to Trafalgar Square, where they sat on the roundabout on the edge of Whitehall while drummers from the XR Samba Band played near the base of Nelson's Column.
The Metropolitan Police said protesters had caused significant traffic disruption with more on a second day of action on Sunday.
James Harvey, a project manager from Salhouse who was live streaming from the protests on the Norwich XR social media, said: “We have done a few roadblocks. There has been quite a lot of disruption on Oxford Street and Regent Street.
“We don’t really want to be causing disruption but it seems to be the only way to make the government listen and take action.”
Extinction Rebellion has vowed to "block areas of the city for as long as possible" every day for at least a week, and on the next three weekends.
The environmental activist group said it was holding training in non-violent action and resistance tactics.
Mr Harvey said: “They call us dangerous radicals, among an abundance of other names, but actually it was António Guterres, UN secretary general, who this week said the real dangerous radicals not are people like us, but the fossil fuel companies and the governments who want to put the future at risk with new oil and gas projects.”
Extinction Rebellion and Just Stop Oil activists have also been blocking access to oil terminals for over a week causing disruptions to fuel supplies including shortages at some Norfolk filling stations.
Hannah Höchner, a lecturer from the University of East Anglia, also taking part in the London protests, said: “The time to stop fossil fuels was yesterday. We can't continue to let the financial interests of a powerful few define the course of life on this planet.”
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