The Metropolitan Police expressed “regret” at the arrest of six anti-monarchy protesters on Coronation Day.
Republic Chief Executive Graham Smith, who was among the group, said he has now received a personal apology from the police officers.
He said he did not accept the apology and would take legal action after no charges were filed against him.
The Met too Certain It used a controversial new law to detain the group.
Smith said the chief inspector and two other officers visited his home in Reading on Monday evening to issue the apologies.
“They seemed somewhat embarrassed to be honest,” he told the PA news agency.
“I told the record that I will not accept an apology. We have a lot of questions to answer and we will take action.”
Smith earlier said he wanted a “full investigation” into the “disgraceful episode”.
The Met said the review found there was no evidence that the six protesters, who were taken into custody when their car was stopped near the route of the procession, were planning a “lock-up,” a now-banned protest technique.
Recent changes to the law, passed last week, make it illegal for protesters to use equipment to secure themselves with things like handrails.
The newspaper said the group of six were arrested after items were found in a car that officers had reasonable grounds to believe could be used as locks on the devices.
But the force said it was “unable to prove its intent to use it to shut down and disrupt the event”.
A man in the group was also arrested for possession of a knife or pointed article.
The Met said it was “not clear at the time” to the arresting officers that “at least one of the group that stopped was engaging with the police” about staging a legal protest before the coronation.
“We regret that these six people who were arrested were unable to join a larger group of demonstrators in Trafalgar Square and elsewhere on the procession route,” the statement continued.
Now she has said that all 6 people have had their bail voided and has confirmed that no further action will be taken.
Smith said earlier Monday that he spent months consulting with officers about his group’s protest plans, and said in a statement on Twitter that his group “will be speaking to attorneys about taking legal action.”
He said he was held for 16 hours on the morning of the coronation after he was stopped by officers who suspected he and members of the group had “locks on” devices to attach themselves to inanimate objects.
“They also said they had intelligence, which is not true,” he told BBC Radio 4’s Today programme.
“If they had intelligence, their intelligence officers were either lying or incompetent because there was no discussion, reasoning, email, letter, or anything that indicated any intent to do anything disturbing.”
Mr. Smith added that after months of discussions with the Met, “the force said over and over again, up until Friday, that they had no concerns about our protest plans, that they were well aware of what we were going to do and that they would reach out to us and don’t bother us.”
He continued, “They have repeatedly lied about their intentions, and I believe they had every intention of arresting us before doing so.”
Mr. Smith also rejected suggestions that his arrest, along with other protesters, was necessary to limit disruption to the coronation.
Shadow housing minister Lisa Nandy said “it is clear that something has gone wrong” in the handling of Mr Smith’s case, and expressed support for a review into the matter, which had been requested by the Mayor of London, Sadiq Khan.
But she said Labor was not committed to a “wholesale repeal” of the new law introduced by the Conservatives last week, which has been criticized for suppressing the rights of peaceful protesters.
She told BBC Breakfast: “One of the questions we have is ‘Why was this group in apparent contact with the Metropolitan, informing them of their plans, and yet they ended up being arrested and prevented from protesting?'” “.
“If there is a problem with the legislation, of course we will correct that in government, but we are not into mass repeal of legislation without first understanding the actual problem.”
Earlier, Police Union President Ken Marsh said the officers were “policing without fear or favour”, insisting the force had done a “fantastic job” in saving Coronation.
He told the Today show: “We have to consider whatever is at that moment in front of us. If there are individuals who intended to cause an incident that affects others near or around them…we take action to deal with it.”
“Protest can happen in this country, but we have to balance and deal with that level at which you do protest.”
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