POLICE have been profiling peaceful republican campaigners over fears they seek to disrupt the coronation ceremony.

An investigation by The Mirror found that forces have been observing and filming members of the campaign group Republic ahead of the event on May 6.

Dai Davies, the former head of the Royalty and Special Protection branch of the Metropolitan Police, which provides security services to the royal family and government officials, claimed the event was the biggest threat to the monarchy in 50 years.

He said: “It is clear the threat to the monarchy is as big as it has been in the last 50 years - and the potential is as big because of the rise of Irish dissident groups and the increased action of anarchist campaign groups.

“This unique set of circumstances has piled pressure on services which are already stretched to the limit".

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Republic campaigns for the abolition of the monarchy and its replacement with an elected head of state.

The group, which claims to have the support of more than 80,000 republicans, plans to host a peaceful protest in London on the day of the coronation.

However, members were filmed by North Yorkshire police during a similar event outside York Minster cathedral last Thursday ahead of an appearance by King Charles at the Maundy Thursday Easter service.

A spokesperson for the police force said: “It is standard practice for the police to use evidence gatherers.

“This is to ensure planned protests remain peaceful and lawful.”

But Republic campaigner Graham Smith described the actions of the police as “chilling”.

“We’re expecting at least a thousand people at our protest on Trafalgar Square on May 6,” he said.

“We will be loud, visible and unmissable, directly challenging the coronation and the monarchy.

“We fully expect the police to live up to their assurances that the protest will be allowed to carry on, but these latest actions and previous arrests may well have a chilling effect on what is lawful and peaceful protest.”

It comes after a student, who is not connected with Republic, was found guilty of threatening behaviour after throwing eggs at the King during a walkabout in York last year.