TOPSHOT - Climate change activists listen to speeches at their encampment blocking the road junction at Oxford Circus in the busy shopping district in central London on April 18, 2019 during the fourth day of an environmental protest by the Extinction Rebellion group. - London commuters faced further disruption on Thursday as climate change protests continued to bring parts of the British capital to a standstill, leading to over 300 arrests. Demonstrators began blocking off a bridge and major central road junctions on April 15 at the start of a civil disobedience campaign calling for governments to declare an ecological emergency over climate change, to reduce greenhouse gas emissions to zero by 2025, halt biodiversity loss and be led by new "citizens' assemblies on climate and ecological justice". (Photo by Tolga AKMEN / AFP)TOLGA AKMEN/AFP/Getty Images