More than 100 people have been arrested across the UK at events related to Palestine Action, in the third week of demonstrations since the group was banned as a terrorist organisation.

Demonstrations were held in London, Manchester, Edinburgh, Bristol and Truro on Saturday as part of a campaign coordinated by Defend Our Juries.

In London’s Parliament Square, beside the Mahatma Gandhi statue, police officers surrounded people at an event at which signs were held that read “I oppose genocide, I support Palestine Action”.

Officers confiscated the placards and searched the bags of those arrested. Some people were carried away while others were led away in handcuffs.

The Metropolitan police said 55 people had been arrested in Parliament Square under section 13 of the Terrorism Act 2000 for displaying placards in support of Palestine Action.

The force added a further nine people were arrested for supporting Palestine Action within a separate large-scale march to Whitehall by the Palestine Coalition.

Defend Our Juries said on X: “The UK government is complicit in Israel’s genocide against Palestinians. They are attempting to silence those who expose this complicity.”

A woman who was detained in Parliament Square said: “We demand that Palestine Action is de-proscribed.

“Our government is not only arming a genocide, they are using terrorism laws to silence people who speak out.

“Palestine Action are campaigning for peace. They are dismantling weapons factories.”

Greater Manchester police said they arrested 16 people, who remained in custody for questioning. Avon and Somerset police said 17 people were arrested during a protest in Bristol.

At Truro Cathedral in Cornwall, eight people were arrested after protesters gathered to show support for Palestine Action. .

Devon and Cornwall police said in a statement that about 30 protesters were involved in a “peaceful” Defend Our Juries demonstration.

“A number of placards which were contrary to the law remained on display despite police advice,” the force said. “Eight people, two men and six women, were arrested on suspicion of offences under section 13 of the Terrorism Act 2000. They remain in police custody.”

At a high court hearing on Monday, the co-founder of Palestine Action, Huda Ammori, will ask for permission to challenge the home secretary’s decision to ban the group under anti-terrorism laws.

UN experts, civil liberties groups, cultural figures and hundreds of lawyers have condemned the ban as draconian and said it sets a dangerous precedent by conflating protest with terrorism.

More than 70 people were arrested last week at demonstrations across the UK where references to Palestine Action were allegedly made.

Police Scotland arrested a man in Glasgow on Friday “for displaying a sign expressing support for a proscribed organisation”.

The sign read “Genocide in Palestine, time to take action” with the words “Palestine” and “action” larger than the others. Another man wearing a T-shirt with the same slogan was charged with a similar offence last weekend at the TRNSMT music festival in Glasgow.

The home secretary, Yvette Cooper, announced plans to ban Palestine Action last month, days after activists from the group broke into RAF Brize Norton and defaced two military aircraft with spray paint.

The ban means Palestine Action has become the first direct action protest group to be banned under the Terrorism Act, placing it in the same category as Islamic State, al-Qaida and the far-right group National Action.