The most complex security operation ever is underway

The most complex security operation ever is underway

The most complex security operation London has ever seen is underway.

The funeral will be attended by many world leaders and members of royal families.

Britain's counter-intelligence and security agency MI5 and the intelligence and security service Government Communications Headquarters (commonly known as GCHQ), are working behind the scenes with counter-terrorism police to ensure the safety of the public and world leaders, who are due to arrive in London in the coming days to attend the Queen's funeral.

The London police have received reinforcements from forces across the country, and members of the military and civil defense are also involved in security protocol.

In the hours and days ahead of the funeral on Monday, the Japanese emperor, kings and queens, the US president, and heads of state from across the globe will assemble in London. They will then all go to Westminster Abbey, which does not have any permanent security perimeter, for a very public funeral.

All of this will be played out in front of hundreds of millions of television viewers around the world, providing a tempting target for international terrorists.

"It has required a security response unprecedented in scale. MI5 and GCHQ are working behind the scenes with counter-terrorism police, the Metropolitan Police has reinforcements from forces across the country, and military personnel and civilian stewards are all playing a role", BBC writes. For now, the most vulnerable point is the queue of people waiting to pay their last respects and cross Lambeth Bridge over the Thames to reach the Palace of Westminster. As part of the first line of defense against the terrorist threat, police are asking citizens to look out for themselves and others, to be vigilant and trust their instincts, and report anything that does not feel right.

In order to protect the entire lines of people who want to say goodbye to the Queen, the government has hired hundreds of security guards from private companies.

The government has hired hundreds of stewards from private security firms to help with queue management. Some 1.500 military personnel have also been deployed since Tuesday night, among them Gurkhas and Paratroopers, Royal Navy Police and Royal Military Police, and RAF personnel in their blue-grey uniforms. A military Wildcat helicopter has made several flights over Westminster.

Behind the scenes, the security service MI5 is watching for any changes of behaviour by "subjects of interest", people suspected of involvement in violent extremism and terrorism. GCHQ will continue to monitor all forms of telecommunication. Armed police officers with binoculars have already been visible on rooftops in Westminster. The lines of people are monitored by special officers trained to identify people who may be preparing a terrorist attack. Police officers monitor footage from hundreds of surveillance cameras, and additional surveillance cameras are installed in risky places or where there are gaps in coverage.

Dogs specially trained to sniff out explosives and firearms are passing periodically through the crowds. The massiveness of the security operation has been compared by many to the Olympic Games held in London in 2012, but the BBC notes that citizens then mostly had to pass through security checkpoints, while now such a checkpoint is located only at the entrance to Westminster Hall, and people wait in line for hours before they get to it.

Thousands of police officers are being deployed in central London each day, but the Met were keen to emphasize the number of reinforcements being provided by other forces. They do not want the people who live in London to think that normal day-to-day policing has been abandoned.

Under what is known as "mutual aid", the Met are borrowing hundreds of officers from forces outside London - from as far away as Scotland and Northern Ireland.

These are being provided under longstanding plans for a national mobilization for the monarch's funeral, which include a wide range of specialist officers. For example, explosives sniffer dog teams from West Yorkshire and Lancashire have been patrolling the Mall this week.

It can also be compared to the funerals of Queen Elizabeth the Queen Mother and Diana, Princess of Wales, but the extraordinary number of heads of state visiting the capital for this event makes it much more complicated.

The threat has also changed. What are known as "lone actor" attacks using vehicles as weapons, or knives that can be bought from supermarkets, have become commonplace in the last decade.

The funeral of Queen Elizabeth II, who died on September 8, will be held on September 19 at Westminster Abbey in London.