Marine Robotics have created vessels called Ghost Guard which can patrol the seas along pre-programmed routes, overseen by a single, human controller on shore. "They could go alongside, there's a loudspeaker and a microphone so they could have a conversation with the vessel," said Mr Henderson. "And if they feel that there's something suspicious then they could call up a naval patrol vessel." "If the vessel gets lost or damaged or sunk, then there's no loss of life," he added. "If the robotic vessel goes alongside a suspicious-looking boat, and they suddenly open fire or throw hand grenades, or fire a rocket-propelled grenade at the vessel to take it out, then yes, there's a cost factor but nobody's lost their lives." Mr Henderson said that the dispensability of such craft makes them particularly suitable to the changing nature of world piracy, including the area of people smuggling.  "A normal naval patrol boat, if he gives chase to a smuggler often has to stop because the smuggler will start to throw people overboard. It's a ploy they often use, and, of course saving lives is a priority for the navy boat. "But with a remote piloted vessel, even if the navy has to stop, the robotic vessel can continue the chase right back to its harbour, or even follow it into a bay where it starts putting people ashore.  "And of course then the smugglers' position can be reported back to the mother vessel." [BBC News]