They also temporarily blocked Piccadilly Circus.
Police have arrested more than 100 environmental protesters overnight as the climate demonstrations that brought chaos to central London enters its second day.
The disruption follows similar action last November when thousands of protesters occupied five central London bridges.
But Shell's headquarters in Lambeth, southeast London, became targeted.
"Intentional arrests for criminal damage allow Extinction Rebellion to take this core strategy into the courts", the group said in a statement.More news: Ex-DNI chief: 'Stunning and scary' that Barr would raise spying allegation
Extinction Rebellion plan to carry out disruption protests during tomorrow and Wednesday's morning rush hours.
Trees and trucks were used to block the busy Thames crossing as the protests kicked off.
Organisers said: "The worldwide rebellion begins and Extinction Rebellion will be bringing London to a standstill for up to two weeks".
The movement, which is demanding the British government takes urgent action on climate change and wildlife declines, has received support from actress and activist Emma Thompson and former archbishop of Canterbury Dr Rowan Williams.
The campaign group said that "over 100 fearless rebels" had been arrested, some willingly.More news: Ilhan Omar says Trump’s actions are inciting death threats
Extinction Rebellion wrote to Prime Minister Theresa May on Monday outlining their demands and asking for face-to-face talks, warning that they will escalate their disruptive actions over the coming weeks unless the government acts.
"We wish to make peace with ourselves by making peace with our neighbour Earth and with our God", he said. One Shell spokesman told CNN: "We respect the right of everyone to express their point of view, we ask only that they do so with their safety and the safety of others in mind".
"We've got 12 years to act before there is irreversible damage to the environment and we start to see catastrophic changes".
Savannah, a protester for Extinction Rebellion, defended the protests and said the group want to start important conversations.
On Tuesday, the Metropolitan police said it had arrested 113 protesters overnight but demonstrators said all four sites remained under their control.More news: Klobuchar Releases Taxes, Urges Trump to Do Same
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