President Joe Biden and dozens of other world leaders will attend the Queen’s funeral as preparations are made for what could be the “biggest policing and protective operation the UK has ever mounted.”
Monarchs and heads of state from countries around the globe are expected to gather in Westminster Abbey for a solemn gathering on a scale seldom witnessed in recent decades.
Biden said on Friday he will be present, although the date has yet to be confirmed.
Thousands of police will be on duty every day in the capital as crowds gather at Buckingham Palace and nearby Green Park to pay their respects, and the force has urged people to “remain vigilant”.
The Queen’s coffin will lie in state for several days ahead of the event.
Nick Aldworth, who led the “protect and prepare” strand of national counterterrorism policing until his retirement in May 2019, said the events would take place in a “very different threat world” than the deaths of Diana, Princess of Wales, and the Queen Mother.
“This will be probably the biggest policing and protective operation the UK has ever mounted,” he told The Independent.
“It just takes one car, one person to do something abhorrent and not only have you disrupted a constitutional event, people will be injured and killed.”
It comes months after a man armed with a crossbow allegedly travelled to Windsor Castle and threatened to kill the Queen.
In 2017, a sword-wielding Isis supporter attempted a terror attack at Buckingham Palace, while two members of a neo-Nazi terrorist group were jailed for inciting attacks on Prince Harry in 2019.
Owen West, a retired chief superintendent who specialised in public order, said police would be working to ensure the public can “express their grief” safely.
“It will be focused around engagement and dialogue with those in the crowd, sharing information that might help them, keeping essential routes free,” he told The Independent.
“Large crowds, these days, represent a potential threat to hostile acts so there will be an eye on risk assessment and measures to help protect the body of a crowd against that potential.”
Roads have been closed to form secure barriers around crowded sites, with barriers and other “hostile vehicle mitigation” measures put up.
A significant armed operation will be in place for the Queen’s state funeral, including rooftop snipers guarding the procession and patrols on the ground.
Scotland Yard said it had initiated “well-rehearsed policing plans” but has not yet confirmed whether it will pull officers in from other parts of the country to bolster its ranks.
A spokesperson said requests under “mutual aid” protocols will almost certainly be made over the coming days, and that the National Police Coordination Centre would be organising officer movements, rest days, pay, and arrangements for hosting volunteer officers.
“During Operation London Bridge, it is expected that the overall policing operation will last for between 10 to 14 days, involving support from forces across the UK, and utilising multiple policing capabilities,” a spokesperson added.
“Due to the nature of Operation London Bridge, which will involve a great number of foreign dignitaries and large crowds, a wide range of police capabilities and specialisms will be called on to assist with the security operation being led by the Metropolitan Police.”
Police leaders said the forces most affected by the arrangements have “longstanding” plans in place to cope with the extra demand.
A spokesperson for the National Police Chiefs’ Council added: “Police forces have business continuity plans in place to ensure they are prepared to assist with this operation, in addition to continuing their core service to the public, keeping communities safe.”
Cross-government procedures originally drawn up in the 1960s under the name Operation London Bridge have been updated and reviewed over the years.
Mr Aldworth said he had first seen Operation London Bridge, then “a dusty ring binder on a shelf”, over 20 years ago and that “current threat methodologies” had changed.
He said he was not aware of a comparable event that had taken place since the main terror threat to the UK became “lone actors”, often using vehicles and knives, rather than bombings and complex plots directed by terror groups.
The former senior Metropolitan Police officer said that crowds of people present a potential target, as well as high-profile attendees at commemorative events.
He recalled that while working on the 2012 London Olympics, mutual aid was implemented to “bring in pretty much every armed officer in the country” to guard international VIPs because of a shortage of protection officers.
Mr Aldworth said that despite the expectation that attendees will be well-intentioned mourners, in tight crowds police “haven’t got a chance of differentiating between people” who get too close to the funeral procession or dignitaries.
Ahead of the funeral, officers are being posted outside key locations, including major railway stations, the royal parks and outside royal residences in London.
Road closures are being put in place around Buckingham Palace and crowded areas as part of the security arrangements, and the public have been asked to remain vigilant.
Deputy Assistant Commissioner Stuart Cundy said: “This will be an extremely poignant moment for the nation, and I know people will want to pay respects and celebrate the Queen’s dedication to public service.
“Working closely with the City of London Police and British Transport Police, the Met will now coordinate and deploy a comprehensive policing plan in London. This operation will be highly visible, particularly in Westminster and areas around Buckingham Palace and St James’s Park.
“A great number of police officers will be on duty during this period, to ensure the safety of those visiting London and to deter any potential criminality.”