Police arrest three people outside insurer of Israeli arms maker Elbit, including Thunberg for holding placard.

British police have arrested Swedish activist Greta Thunberg and two other people at a pro-Palestine protest in central London, according to campaign group Defend Our Juries.

The group said Thunberg was arrested on Tuesday at the Prisoners for Palestine protest held in the heart of London’s Square Mile financial district outside the offices of Aspen Insurance, which provides coverage for Israeli defence contractor Elbit Systems.

The group said Thunberg had arrived after the protest began, and it shared video footage of the activist holding a sign reading, “I support the Palestine Action prisoners. I oppose genocide.” Thunberg has called Israel’s war in Gaza a genocide and has twice joined flotilla campaigns to try to break Israel’s siege of Gaza.

The City of London Police, which polices the financial district, confirmed that a 22-year-old woman, a description corresponding to Thunberg, was arrested for displaying a placard “in support of a proscribed organisation (in this case Palestine Action) contrary to Section 13 of the Terrorism Act 2000”.

This is the latest protest in solidarity with activists from the Palestine Action group, six of whom are currently on hunger strike in British prisons with two now hospitalised. The direct action group has been proscribed as a “terrorist organisation” by the United Kingdom’s government.

Defend Our Juries said Tuesday’s protest was held to draw attention to Aspen Insurance’s “complicity in genocide” and to express solidarity with prisoners affiliated with Palestine Action.

Two others, a man and a woman, were also arrested at the protest although they had “glued themselves nearby”, according to the City of London Police, which described damage with “hammers and red paint” to “a building on Fenchurch Street”, where the offices of Aspen Insurance are located.

Defend Our Juries confirmed the damage, saying in a news release that two activists “covered the front of the building with symbolic blood-red paint, using re-purposed fire extinguishers” before attaching themselves to the front of the building in the aim of “drawing attention to Aspen’s complicity in Genocide, disrupting their business, and closing down the building”.

The group said Aspen Insurance, a global insurer and reinsurer, was targeted because of its affiliation with Elbit Systems UK, a subsidiary of Elbit Systems, which is Israel’s largest arms producer. It describes its drones as “the backbone” of the Israeli military.

Palestine Action protesters had targeted one of the UK subsidiary’s operations in Bristol last year. Among their five key demands, the group’s hunger strikers want the manufacturer, which has several UK factories, to be shut down.

Defend Our Juries said in its news release that Deputy Prime Minister and Justice Minister David Lammy has “refused to speak to legal representatives of the hunger-strikers, or their families”.

A few days earlier, Thunberg had voiced solidarity with the hunger strikers on Instagram, saying: “It is up to the state to intervene, and put an end to this by meeting these reasonable demands that pave the way for the freedom of all those who choose to use their rights trying to stop a genocide, something the British state has failed to do themselves.”

A Palestine Action spokesperson said in relation to her arrest that it was not clear whether police had “made another one of their mistakes in interpreting the crazy ban on Palestine Action” or whether they had “turned anyone expressing support for prisoners locked up beyond the legal time limit for taking action to stop a genocide into alleged terrorists”.