The arrest of protesters during the coronation has been branded a "direct attack on democracy" that shows the right to peacefully demonstrate "no longer exists", the leader of an anti-monarchy group has said.
After 52 people were detained for conspiracy to cause a public nuisance and other public order offences, Republic's Graham Smith said "every police officer involved on the ground should hang their heads in shame".
Among the group's members who felt "targeted" and silenced were nine people that held up signs reading "Not my King" at the Mall, moments before the procession left Buckingham Palace.
Although not arrested, they were whisked out of sight of the King and Queen into St James's Park to be searched by Welsh police officers, outnumbering them roughly two-to-one.
Officers surrounded them and exchanged words before rifling through their pockets - some protesters faced the wall with their hands up in front of them.
Protester Harvey Woolf said: "I wasn't very happy about the searches, I think we had been targeted because they didn't want our message to get out."
He continued: "What we are annoyed and disappointed about is that it was timed exactly to coincide with the point at which the carriage went down the Mall."
The 66-year-old said police told him the protesters were suspected of carrying paint, but an officer told Sky News they led the Republic members away to avoid a "hostile environment" created by the crowds.
Royal supporters had booed and shouted "shame on you" when the protesters were initially marched away from the Mall.
The Met and Welsh police were asked if it was policy to remove people who are subject to a "hostile environment", rather than those creating it, but were not able to immediately respond to a request for comment.
The protesters had been standing still holding bright yellow signs above their heads, several rows back from the barricades lining the Mall, to object to what they called hereditary privilege and power.
One of them, Ronda Evans, 69, said: "The monarchists turned on us and started booing and growling at us when they saw us surrounded by the police officers."
More from the King's coronation:
William receives gift as Prince and Princess of Wales meet royal fans
London mayor calls for 'urgent clarity' from Met over policing of coronation protests
Moments that mirrored Queen Elizabeth II's coronation
Republic were not the only group at the centre of a dispute over police behaviour yesterday, with Westminster Council volunteers handing out rape alarms reportedly arrested.
The arrests come in the wake of the Public Order Act, given royal assent on Tuesday, which handed the police more powers to curtail demonstrations, such as allowing officers to search people for items including locks and glue.