LONDON — London police arrested at least 200 people on Saturday during the largest protest in support of Palestine Action since the group was banned last month under the UK’s anti-terrorism laws.

The Metropolitan Police said more arrests were expected at the demonstration in Parliament Square, rejecting organisers’ claims that only a “fraction” of attendees had been detained.

“That claim simply isn’t true,” the force said, adding that anyone openly displaying support for Palestine Action “was either arrested or is in the process of being arrested.”

The British government banned the group in early July, days after activists broke into an air force base in southern England, causing an estimated £7 million ($9.3 million) in damage to two aircraft.

The interior ministry accused the group of other “serious attacks” involving violence, injuries, and significant property damage.

Critics, including the United Nations, Amnesty International, and Greenpeace, have condemned the move as legal overreach and a threat to free speech.

A coalition called Defend Our Juries, which organised Saturday’s protest, said “unprecedented numbers” had risked arrest and possible imprisonment to defend civil liberties.

“We will keep going. Our numbers are already growing for the next wave of action in September,” the group said.

Demonstrators gathered near Parliament waving Palestinian flags and holding signs reading “oppose genocide, support Palestine Action.” Some applauded those being arrested and shouted “shame on you” at police.

“This government has gone too far. I have nothing to feel ashamed of,” said Richard Bull, 42, a wheelchair user at the protest.

Since Palestine Action was outlawed on July 5, UK police have made dozens of similar arrests. Under anti-terror laws, membership or public support for the group is a criminal offence punishable by up to 14 years in prison.

Seven people have been charged in Scotland and several others in England and Wales. — Agencies