Snipers on rooftops, air cover and facial recognition technology are among security measures in place for Operation Golden Orb – the security effort for the coronation.
It’s all being coordinated on the day from a bomb-proof basement across the Thames from Westminster Abbey.
Along with more than 11,000 police, it’s intended to provide iron-clad protection for the King’s big day.
Tactical firearms units with Heckler and Koch MP5 sub-machineguns and Glock 17 pistols will be on patrol, and there will be armed response vehicles on standby.
Meanwhile, spotters will take up position on rooftops alongside officers with sniper rifles.
Senior officers also plan to use facial recognition tech for the first time to identify terror suspects and criminals who may attempt to mix with the crowd.
However, much of the work has been done in the weeks building up to the event, with MI5 focusing surveillance on “subjects of interest” who have shown an interest in the Royal Family.
Air cover will be provided by three twin-engine Airbus helicopters from the Metropolitan Police Air Support Unit based at Lippitts Hill in Essex, backed up by aircraft from other forces.
They can also call on the National Police Air Service, which has four Vulcan 68R fixed-wing aeroplanes.
Hostile vehicle barriers have been moved into place to stop terrorists driving into the crowd and there will be a double layer of crowd control barriers to make it harder for an attacker to reach the King.
Sniffer dogs will conduct random checks for explosives as the public arrive at transport hubs and there will be officers on horseback.
Man with knife outside palace raises concerns
The security effort comes as police were given greater powers to tackle disruption to the coronation under new laws that came into force on Wednesday.
However, the arrest of a man outside Buckingham Palace on Tuesday has highlighted security concerns.
He was arrested after throwing what is suspected to be shotgun cartridges into palace grounds, the Metropolitan Police said.
A precautionary controlled explosion was carried out outside the palace and the man was held on suspicion of the possession of an offensive weapon, the force added.
Officers said a knife was found on him but he did not possess a gun.
The arrest has highlighted concerns, as has an escalating series of road-blocking protests by the Just Stop Oil campaign group.
But police are alert to the potential for a much bigger threat from terrorists who could use the global live television coverage to publicise their aims.
The new legislation carries up to a year in jail for demonstrators blocking roads, airports and railways.
Anyone locking or gluing themselves to buildings or objects risks six months behind bars.
Police can also stop and search anyone they suspect is planning to cause disruption – one of the powers given royal assent by the King on Tuesday.
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Details of the new laws were outlined in a Home Office letter sent to various protest groups, some of whom reportedly condemned the move as “intimidatory”.
Police will have assembled an intelligence database of likely demonstrators and in the past, ahead of major public events, have visited known individuals to try to ask them about their intentions.
Anti-monarchist Patrick Thelwell, 23, who was fined last year for throwing an egg at the King in York, is urging others to join him at a Coronation Day “Not My King” protest in central London, but has asked demonstrators not to bring eggs.
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Metropolitan Police Deputy Assistant Commissioner Ade Adelekan said in a media briefing ahead of the coronation that the force is extremely proud to be policing proceedings in “the event of a lifetime”.
He said there will be hundreds of thousands of visitors coming to London for the event and said Saturday would be “one of the most significant security operations that the Met has led”.
Around 9,000 non-specialist police officers will be on duty, with another 2,500 officers specialising in areas such as close protection, firearms and search – putting the total deployment in excess of 11,500.
Meanwhile, Commander Karen Findlay, who is leading the policing operation as Gold Command, said there are more visitors classed as “V-VIP” attending the coronation than the Queen’s funeral.
She added that the deployment is also taking place in a shorter time period than for the funeral and around 10,000 military personnel will be present for the event.
Government in ‘no way complacent’
It comes as security minister Tom Tugendhat said the government is “in no way complacent” about security surrounding the King’s coronation after the arrest outside Buckingham Palace.
He said he was “very proud” of the way the police responded to the incident.
Mr Tugendhat told Kay Burley on Sky News: “I’m very glad to see that the police reacted incredibly quickly, incredibly professionally, to the incident last night.
“We’re in no way complacent. And I’m very, very proud of the response that the police have done.
“The intelligence services, the police and others have been working on this extremely effectively for months.”
Buckingham Palace confirmed neither the King nor Queen Consort were at the palace at the time of the incident.
Scotland Yard said they are not treating the incident as terror-related.
Asked how much security for the coronation would cost the taxpayer, Mr Tugendhat was unable to give a figure.
He said: “It’s very difficult to pull that out as a separate figure for the simple reason that we’ve got an enormous amount of effort going in for a major incident like this in different parts of the country – because there are people getting together in streets, there’s people getting together in gatherings across the country because this is a moment of national celebration.
“What I think is worth looking at, though, is how much this is bringing to the country in terms of the number of tourists who are coming, the amount of attention that is coming and indeed, I hope, the amount of business that will be generated by heads of state and government and other business people coming to the UK at this time to see what we offer.”
Pressed on figures of at least £100m just for security, Mr Tugendhat said: “It’s not a figure that I recognise, sorry.”
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He said: “Forgive me for not being able to break it down at this point.
“The reason I don’t want to do that is because there’s police forces around the country who are doing different things and answer slightly differently through their own different structures.”
He said he did not have a number for how much it was costing the Metropolitan Police, but added: “What I’ve been doing is making sure that the Met are ready, and that means preparing with them and the National Crime Agency and the intelligence services to make sure they have all the resources they need.
“We have spent an awful lot of time over the last several months preparing for any number of different threats because the reality is this is a very complex event.”