Drones could be used by terrorist groups as "simple, affordable and effective

airborne improvised explosive devices," says a report by London-based think tank

the Remote Control Project.

The authors suggest manufacturers should program drones with the GPS coordinates of no-fly zones.

The British government should also relax regulations on radio frequency jammers,

they add.

In addition, they advise tighter UK licensing regulation.

Currently in the UK, anyone can own and operate for non-commercial purposes a

drone that weighs less than 20kg (3st 2lb) - and there are hundreds on the market.

"A range of terrorist, insurgent, criminal, corporate and activist threat groups

have already demonstrated the ability to use civilian drones for attacks and

intelligence gathering," the report reads.

"The best defence against the hostile use of drones is to employ a hierarchy of

countermeasures encompassing regulatory countermeasures, passive countermeasures and active countermeasures."

It suggests that these could include:

limiting the payload capacity of commercial drones
devising a security alert system when drones appear in no-fly zones
the development of "innovative less-lethal anti-drone systems"

However, David Dunn, professor of International Politics, at Birmingham University, told the BBC that licensing may not deter terrorists.

"Law abiding citizens are likely to register, but it would be very difficult to

stop terrorists and other criminals from purchasing drones abroad and then using

them here," he said.

"Up until now it was expensive and required skill to be able to fly an aircraft - which acted as a form a regulation in itself.

"Now, you can fly these things relatively easily over people's heads."The report also lists recent examples of suspicious activity involving drones: Unidentified drones have been flown over various landmarks in France,

including the US Embassy and the Eiffel Tower
The Metropolitan Police recorded 20 suspicious drone-flying incidents around

London between January 2013 and August 2015
So-called Islamic State has released videos showing drones being used for

reconnaissance in Iraq

The authors of the report, members of a non-profit group called Open Briefing

which describes itself as "the world's first civil society intelligence agency",

admit that their suggested countermeasures are "not foolproof".

"The technology of remote control warfare is impossible to control," the report

says.

"The ultimate defence is to address the root drivers of the threat in the first

place."（From：BBC）