On Saturday, 9 September 2025, a large gathering took place outside Parliament Square in London as demonstrators voiced opposition to what they described as genocide in Palestine. The event, intended as a peaceful protest, quickly drew a heavy police presence. Tensions rose after it became clear that the UK government had, in July, officially proscribed the group under the Terrorism Act 2000 — a move that made public expressions of support for the organisation a criminal offence carrying penalties of up to 14 years in prison.

As the protest unfolded, officers began detaining individuals seen holding placards or displaying messages linked to the banned group. Witnesses reported that people were being arrested simply for carrying signs, with several participants approached by police within minutes of their arrival. The measures sparked debate about the balance between national security laws and the right to peaceful assembly in a democratic society.

Video footage from Parliament Square captured the scale and intensity of the crackdown. Officers, working in coordinated formations, moved through the crowd to seize signs and disperse demonstrators. In total, more than 300 people were arrested during the operation, their placards confiscated on the spot. The scenes left a lasting impression on observers, many of whom questioned whether the government’s response risked undermining civil liberties.