Smart motorways: How safe are they?

The technology behind England's smart motorway network stops working on a regular basis, the BBC has discovered.

Figures obtained by BBC Panorama have revealed hundreds of incidents when crucial safety equipment was out of action.

National Highways - the agency in charge of smart motorways - says the latest data shows that "smart motorways are our safest roads".

It says safety is its highest priority, and there are well-rehearsed contingency plans to deal with power outages.

Claims that smart motorways tech leaves drivers at risk - read more here.