Islamic State could use drones to carry out a terror attack against the UK, a leading security expert warned, as ministers confirmed the group was arming the unmanned aerial vehicles with explosives.
Former head of the navy Admiral Lord West of Spithead, said tighter safeguards were needed for commercially-available drones in the UK, and called for safety switches to be introduced which would prevent the remote-controlled vehicles flying near potential targets.
He also urged the Government to introduce a tougher licensing system for drones which could be adapted to carry lethal cargoes.
The Foreign Office confirmed it had evidence that IS - also known as Daesh - was using the widely available drones for surveillance and propaganda purposes as well as converting them to carry explosives in the Middle East.
Foreign Office Minister Baroness Anelay of St Johns said: "The Government has a range of material, including images, that provides evidence that Daesh has used small, commercially available unmanned aerial vehicles in Syria and Iraq to extend their surveillance capability, produce propaganda material and carry small improvised explosive devices."
Former security minister Admiral Lord West said if the terror group was using the technology in its heartlands it was likely to use drones in the West - where they are more readily available in shops.
He warned: "I don't think our control of drones is as tight as it should be."
He told the Press Association: "If they are using them there, then in fact they are probably even easier to use them here because you can get them so much easier.
"You can pop into any store and buy them. Therefore I am very concerned."
Admiral Lord West said he was concerned about the control of drones in the UK and is pressing the Government about restrictions, asking "is there some way of registering these, is there a way of putting something into the drone so it can't fly into certain areas?".
The use of "geo-fencing" prevents drones from being able to fly over designated areas.
Admiral Lord West said: "There is a thing you can do which makes the drone inoperative if it goes on to a boundary of some area, it just stops being able to function. I think that should be mandatory in drones.
"The other thing is, I think buying drones of a certain size - let's say ones that can carry two pounds weight and above - you should, rather like getting a gun licence, have some way of proving who you are and registering."
Admiral Lord West said IS would look for any weakness: "Daesh is like water at the top of a building, it spreads across and tries to find little gaps it can run through. This will be one of the little gaps it is looking at.
"I think it would be foolhardy for us not to look to our defences for this."
The Department for Transport is talking to manufacturers about the use of geo-fencing technology in their drones.
Ministers are examining the possibility of introducing a drone registration scheme in the UK, similar to the ones already in place in Ireland and the US.
The Civil Aviation Authority advises that drone operators must be able to see the craft at all times and must not fly above 400ft (122m).
Drones fitted with cameras must not be flown within 50m (164ft) of people, vehicles or buildings, or over congested areas or large gatherings such as concerts and sports events.