Queen Elizabeth II: Up to 10,000 daily police to be on duty in London

There is already a heavy police presence outside Buckingham Palace

About 10,000 police officers could be on duty every day in London each day leading up to the Queen's funeral as part of the biggest security operation the country has ever seen.

All leave and training is likely to be cancelled and extra help called in from surrounding forces, former Metropolitan Police commander Bob Broadhurst says.

The City of London Police and British Transport Police have already initiated well-rehearsed policing plans.

The Queen died at Balmoral on Thursday.

The Met will also need extra specialist officers from other forces across the UK, including close protection and firearms, to take part in the meticulously planned and complex security operation.

Mr Broadhurst, who led the policing operation during the Olympics and Paralympics in 2012 when about 10,000 officers were on duty in London each day, expects similar numbers in the lead-up to the Queen's funeral.

The largest annual policing event for the Met is usually the Notting Hill Carnival, during which about 6,000 officers are on duty each day.

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Mr Broadhurst, who was with the Met for 36 years, said: "Clearly you need to manage crowds. Unfortunately, large numbers of people also bring in criminal opportunities, so you have to manage crime.

"You have to manage the basics like lost children, all the other stuff that goes with that.

"Clearly [concerns about] terrorism will be a factor. Security is a big issue right from the outset - not necessarily the more organised terrorist groups but lone individuals, that has to be factored in as well."

A miniature gallery of stamps has been stuck to the railings at Buckingham Palace

Mourners are expected to queue for several hours including overnight to pay their respects to the Queen as she lies in state, expected to be from Wednesday.

Members of the public waited up to 10 hours to see Diana, Princess of Wales and the Queen Mother lie in state following their deaths.

The Met will also be responsible for the protection of public figures and foreign dignitaries who attend the funeral, and dealing with any protests that their visits may trigger.

Mr Broadhurst said: "By the end of the week you start to click in to what will be, I would say almost certainly, the biggest security operation the country has ever seen.

"Practically every nation on earth is going to want to send their king, queen, prime minister or president for the funeral."

The Met's Deputy Assistant Commissioner Stuart Cundy said the force would "now co-ordinate and deploy a comprehensive policing plan in London" which will be "highly visible"

He said: "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."

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