Tens of thousands flooded the streets of London on Saturday in one of the largest demonstrations yet against Israel’s war on Gaza, with protesters denouncing what they called a genocide and expressing solidarity with Palestinians under siege. The march coincided with a rally opposing the British government’s recent ban on the activist group “Palestine Action” under anti-terrorism laws.

Crowds moved towards Downing Street and Parliament Square, where hundreds staged a sit-in holding placards reading: “I oppose genocide, I support Palestine Action.” Police arrested around 150 people, including elderly citizens and people with disabilities, after they openly defied the ban and declared their willingness to be detained. Many accused the government of silencing dissent while enabling Israeli crimes.

The ban on Palestine Action followed a June protest in which activists sprayed red paint on two Voyager aircraft at RAF Brize Norton, in an action symbolising Palestinian bloodshed. Protesters said that, regardless of arrests or legal threats, they would continue to stand in the streets until the killing in Gaza stops and Britain ends its complicity.