Police arrested dozens of demonstrators outside the Labour Party conference on Sunday during a protest in support of Palestine Action.
More than 250 protesters sat outside the conference centre in Liverpool, many holding home-made banners which read: “I support Palestine Action.”
The group was proscribed by parliament last year, making the display of any article in support of it, potentially including signs, a criminal offence under the Terrorism Act.
Scores of police stood by before moving in to start making arrests, telling protesters they were holding up a sign supporting a proscribed organisation.
After asking if they were going to continue holding up the signs, police led people away, telling them they had been arrested under the Terrorism Act.
The arrests, which continued for hours, were criticised by Amnesty International, calling them a “shameful attack on freedom of speech”.
A spokesperson for Defend Our Juries, which organised the protest, confirmed on Monday that more than 150 arrests had been made, saying: “We had hoped the new prime minister, Andy Burnham, would do the sensible thing and bin the ban on Palestine Action given the weight of public pressure to do so and the escalating amount of resources required in enforcing it.
“Continuing the charade of the proscription of Palestine Action is illogical, unsustainable and immoral.
“Hundreds of people, from professions including teachers, pensioners, and healthcare workers, are willing to be arrested today to let Andy Burnham know that it is not enough just to say that Israel is committing war crimes including ethnic cleansing in Gaza, he must take meaningful action to end UK complicity with Israel’s crimes.
“The first step the PM could do today, from the podium of his inaugural party conference is to commit to ending the prosecution and jailing of people as terrorists just for standing up against war crimes and genocide.”
Demonstrators cheered every time someone was carried away by police, chanting “free, free Palestine”.
Kerry Moscogiuri, chief executive of Amnesty International UK, said: “Protesting is one of the most effective tools we have to make our leaders listen to us, but we have seen consecutive governments crackdown on our right to do it.
“The arrests of grandparents, teenagers and everyone in between for holding placards outside the Labour Party conference are a truly shameful attack on freedom of speech.
“The new prime minister can reform our laws so that communities are protected in coming together and demonstrating on the issues they care about. Will he do so?”
An earlier police statement said: “We can confirm that more than 50 people have been arrested so far today at a Defend Our Juries protest near to The Wheel of Liverpool.
“Some of the people in attendance displayed material in support of Palestine Action who have been proscribed as a terrorist organisation. Officers are in the process of making arrests on suspicion of wearing/carrying an article supporting a proscribed organisation.
“Merseyside Police respects everyone’s rights to protest lawfully, while also aiming to keep the peace and ensure the public are safe. The force makes detailed and coordinated plans ahead of such events to ensure it can apply this consistently, fairly and proportionately.”
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