A net of spikes that can stop a lorry in its tracks is the latest anti-terrorist measure to be unveiled by Scotland Yard. The new device, known as a Talon, can bring to a halt a vehicle weighing up to 17 tonnes by puncturing its tyres and is designed to protect crowds at public events.

Using vans or lorries as weapons to crash into pedestrians has become a major terrorist tactic in recent years, with massacres in Barcelona, Westminster and London Bridge taking place in recent months, killing 27 people and injuring scores more.

Both Islamic State and al-Qaeda have called on their followers to carry out vehicle ramming attacks. The new nets have tungsten steel spikes which puncture the tyres of any vehicle, said the Metropolitan Police. The net then becomes tangled around the front wheels of a lorry or van.

It is also designed to ensure that the vehicle skids in a straight line, significantly reducing risk to crowds. Police add the net can be deployed by just two officers in under a minute.

The device was laid out for the first time on Whitehall in London on Sunday morning (10 September) as hundreds of Royal Navy sailors and veterans paraded in front of the Cenotaph. The Met Police added the net is likely to become a familiar sight at events in the capital.

Heavy metal and concrete crash barriers to prevent vehicles being driven into crowds are also becoming a permanent feature of London tourist spots and have already been fitted to nine of the capital's bridges.

Chief Inspector Nick Staley of the Met's protective security operations unit said: "This equipment undoubtedly has the potential to save lives and is just one of a number of measures being taken to provide protection to crowds attending major events in London and reassuring businesses, workers and visitors as they go about their daily lives."

The Talon in place for the first time at Whitehall for the Naval Association Parade this week
The Talon in place for the first time at Whitehall for the Naval Association Parade this week