Experimental kamikaze FPV drones have been developed that can penetrate spaces previously thought safe

On the battlefields of Ukraine, new sights emerge. Thread-like filaments of wire, extended across open fields. Netting rigged up between trees along key supply roads. Both are responses to a hard-to-detect weapon able to sneak into spaces previously thought safe, hi tech and low tech all at once.

At a secret workshop in Ukraine’s north-east, where about 20 people assemble hundreds of FPV (first person view) drones, there is a new design. Under the frame of the familiar quadcopter is a cylinder, the size of a forearm. Coiled up inside is fibre optic cable, 10km (6 miles) or even 20km long, to create a wired kamikaze drone.