Dozens of people have been arrested at protests across the UK against the decision to proscribe Palestine Action as a terror group.

Demonstrations in support of the pro-Palestine activist group took place in London, Edinburgh, Manchester, Bristol and Truro on Saturday.

The Met Police said 55 people were arrested on suspicion of terrorism offences in Westminster for displaying placards in support of Palestine Action. Eight people were also arrested in Truro and 17 in Bristol.

The government proscribed the group earlier this month under the Terrorism Act of 2000, making membership of or support for the group a criminal offence, following a break-in at an RAF base.

Across the country, protesters held placards with the words: “I oppose genocide. I support Palestine Action.”

In London, arrests were made near the Mahatma Gandhi statue in Parliament Square, where as many as 20 police vans attended.

Officers moved in swiftly to arrest those holding the placards, many of whom appeared to be over the age of 60.

One woman claimed to be in her 80s and was walking with a stick. Some were led away while others had to be carried.

Avon and Somerset Police said 17 people were arrested under the Terrorism Act after a demonstration on College Green in Bristol.

It said a further three people would be invited to attend a voluntary interview at a future date.

Devon and Cornwall Police said two men and six women were arrested on suspicion of terrorism offences after protesters gathered near Truro Cathedral.

The force said around 30 people were involved in the peaceful demonstration, organised by campaign group Defend Our Juries.

Earlier, the campaign group said that one of those arrested near the cathedral was an 81-year-old former magistrate.

It also said 16 people were arrested in Manchester.

Police forces in the other locations where protests took place have not yet confirmed the number of arrests they made.

Separately, a march organised by Palestine Coalition took place in London on Saturday.

The Met said 10 people had been arrested so far within that demonstration, including eight people suspected of supporting Palestine Action.

Saturday’s protests came ahead of a High Court hearing on Monday at which the co-founder of Palestine Action, Huda Ammori, will ask for permission to challenge the decision to ban the group.

Last Saturday, 71 arrests were made across the UK at similar protests against the decision.

Palestine Action has engaged in activities that have predominantly targeted arms companies since the start of the current war in Gaza.

MPs voted to proscribe the group after activists broke into RAF Brize Norton in June, spraying two Voyager aircraft with red paint and causing £7m worth of damage. Palestine Action took responsibility for the incident at the time.

Four people have since been remanded in custody, charged with conspiracy to commit criminal damage and conspiracy to enter a prohibited place knowingly for a purpose prejudicial to the safety or interests of the UK.

The incident also prompted a security review across all UK military bases.