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...