UK Police arrest anti-monarchy protesters ahead of King Charles' Coronation: Report

London: The UK police on Saturday arrested six demonstrators, including the head of an anti-monarchy group Republic, hours before the coronation of King Charles III as they had gathered among the crowds lining the procession route in central London, according to a media report.

Footage showed protesters in "Not My King" T-shirts being detained, including Republic's CEO Graham Smith ahead of the Coronation in Trafalgar Square, a public square in the City of Westminster, Central London, the BBC reported.

The demonstrators, including Smith, were arrested by police while unloading placards near the Coronation procession route.

The anti-monarchy group posted photos of officers taking details from them on Twitter.

"So much for the right to peaceful protest," the group said, adding the officers would not give the reasons for their arrest and confirmed their CEO was among them.

Matt Turnbull, one of those arrested, said the straps holding the placards had been "misconstrued" as something that could be used for locking on, the report said.

"To be honest we were never going to be allowed to be a visible force here - they knew we were coming, and they were going to find a way to stop this," he was quoted as saying to the BBC.

Turnbull was later seen being led away in handcuffs, the report said.

King Charles III on Saturday became the 40th British monarch to be crowned at Westminster Abbey in London, surrounded by heavy symbolism of his many passions, including a drive towards more sustainable living, a multi-faith outlook and a great love for India and the wider Commonwealth.

While he ascended to the throne immediately after the death of his mother Queen Elizabeth II last September, the 74-year-old was formally crowned King of the United Kingdom when the Archbishop of Canterbury concluded the religious ceremony by inviting the 2,200-strong congregation and millions watching worldwide to swear allegiance to the new British Sovereign.