How Ukraine’s naval drones hold Russia’s warships at bay

They look like friends messing about in boats. They are anything but. One jumps off a small vessel and stands in the water nudging it around, while others stand on shore watching. A man holding a machine gun looks on, hidden from prying eyes by tall reeds. Suddenly the boat, with no one on it, roars off into the distance, controlled remotely from a white van on the beach. Today the meny are testing the boat, but its next mission will be to attack a Russian target.