On December 23, 2025, Swedish climate activist Greta Thunberg was arrested in London under the UK Terrorism Act. She was holding a placard. It read: “I support Palestine Action prisoners. I oppose genocide.”
The City of London Police confirmed the arrest in a statement, explaining that Thunberg “has been arrested for displaying an item (in this case a placard) in support of a proscribed organisation (in this case Palestine Action) contrary to Section 13 of the Terrorism Act 2000.” The arrest took place outside Aspen Insurance, which reportedly provides insurance services to Israeli weapons firm Elbit Systems.
Palestine Action was designated a terrorist organization by the UK government following a high-profile break-in at RAF Brize Norton in June 2025. Since the ban, more than 2,700 people have been arrested for activities including holding signs, attending protests, and wearing campaign t-shirts. In February 2026, a High Court would rule that the designation was unlawful and disproportionate — but at the time of Thunberg’s arrest, the ban was in force, and the Terrorism Act was being applied to placard-holders.
Thunberg was 22 years old. She was not accused of planning violence, inciting harm, or coordinating illegal activity. She was arrested for publicly saying she opposes genocide.
This is what the criminalization of Palestine solidarity looks like in practice. Not the theoretical argument about where speech ends and incitement begins — but a young woman in handcuffs outside an insurance company, arrested under anti-terrorism law for the content of a sign. The UK government created the legal mechanism. The police applied it. And the High Court, two months later, ruled that the underlying designation was never lawful to begin with.
Thunberg was later released. The 2,700 others arrested before her still await their outcomes.
Britain Arrested Greta Thunberg Under the Terrorism Act for Holding a Sign That Said ‘I Oppose Genocide’
On December 23, 2025, Swedish climate activist Greta Thunberg was arrested in London under the UK Terrorism Act. She was holding a placard. It read: “I support Palestine Action prisoners. I oppose genocide.”
The City of London Police confirmed the arrest in a statement, explaining that Thunberg “has been arrested for displaying an item (in this case a placard) in support of a proscribed organisation (in this case Palestine Action) contrary to Section 13 of the Terrorism Act 2000.” The arrest took place outside Aspen Insurance, which reportedly provides insurance services to Israeli weapons firm Elbit Systems.
Palestine Action was designated a terrorist organization by the UK government following a high-profile break-in at RAF Brize Norton in June 2025. Since the ban, more than 2,700 people have been arrested for activities including holding signs, attending protests, and wearing campaign t-shirts. In February 2026, a High Court would rule that the designation was unlawful and disproportionate — but at the time of Thunberg’s arrest, the ban was in force, and the Terrorism Act was being applied to placard-holders.
Thunberg was 22 years old. She was not accused of planning violence, inciting harm, or coordinating illegal activity. She was arrested for publicly saying she opposes genocide.
This is what the criminalization of Palestine solidarity looks like in practice. Not the theoretical argument about where speech ends and incitement begins — but a young woman in handcuffs outside an insurance company, arrested under anti-terrorism law for the content of a sign. The UK government created the legal mechanism. The police applied it. And the High Court, two months later, ruled that the underlying designation was never lawful to begin with.
Thunberg was later released. The 2,700 others arrested before her still await their outcomes.