Extreme security for royal wedding

Snipers are on rooftops today with soldiers and armed police patrolling the streets below as a $58.8 million ring of steel today surrounds Windsor Castle ahead of the royal wedding.

Police, the Army and undercover members of the security services are ready 'do whatever is necessary' to prevent any attack on Harry and Meghan's big day, including shooting to kill, the Daily Mail reports.

The 2.6-mile route the couple will travel from St George's Chapel to Windsor Castle is lined with sharpshooters on top of buildings and other vantage points. Specialist teams are also patrolling the Thames.

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Police and soldiers carrying automatic weapons will also line the streets ready to fire if necessary and are already patrolling the roads, which have crash barriers used to stop vehicle-based terror attacks.

With the UK's terror threat level at severe the cost of security for the first major royal wedding since 2011 is expected to reach up to £30million and the bill will be picked up by the taxpayer.

Thames Valley Police has asked well-wishers not to bring confetti to the procession amid fears the sight of someone throwing something towards the carriage could spark a security alert.

It is Thames Valley Police's biggest ever operation and they are relying heavily on Scotland Yard and MI5 for support.

It came as superfans camped on the streets overnight to secure their spots to see the procession through the Berkshire town tomorrow.

Armed police and specially trained sniffer dogs are patrolling the streets of the royal town, with squadrons of uniformed officers with machine guns toured the town in rotation.

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Their colleagues are checking drains, bins and any other potential hiding places for bombs as the Berkshire town was turned into a fortress.

Thames Valley Police and the Metropolitan Police - who guard the Royals – used the dress rehearsal yesterday to assess any potential security threats or bottlenecks and crowd surges.

As many as 100,000 visitors are expected to flock to the Berkshire town this weekend - which has a population of 35,000 - to catch a glimpse of the newlyweds.

This article was first published on nzherald.co.nz and is republished here with permission.