A global medical charity is calling for drones to be included in international arms limitations treaties, arguing that on top of the physical harm they wreak they also inflict psychological harm – both when they strike and by causing innocent people to live in fear.
A report by Medact, whose members are health professionals, says there are many reasons to be concerned about the increasing use of unmanned, armed drones.
It says: "In addition to the number of deaths and injuries of innocent civilians, we also have concerns about the psychological damage to people living under the constant threat of drone attack and to service personnel who carry out the assassinations.
"There is also some evidence that medical personnel and others who arrive at the scene to assist the injured have been targeted in drone attacks. This is a war crime."
The most accurate figures on the numbers of civilians killed by drones are from Pakistan, says the report, and they range from light casualties to the large estimates of deaths, including those of children, family members attending funerals and medical personnel, provided by the Bureau of Investigative Journalism. The Bureau says that between 2,985 and 4,533 civilians have died since 2001 in Pakistan, Yemen and Somalia.
Injuries, says Medact, are fewer than deaths, which is unusual in a conflict.
"While more injuries than deaths probably go unreported, this nevertheless gives an indication of the deadly nature of drone attacks and the unnecessary deaths that will occur if mistakes are made in targeting, observation or intelligence gathering," says the report.
"The deaths and injuries suffered by innocent civilians in what are euphemistically called 'surgical strikes' are often underreported."
Women are disproportionately affected by drones, it adds. "What little control they have over their lives is further eroded by a weapon they know could strike at any time."
By the end of last month, Britain had carried out more than 300 drone strikes in Afghanistan. There are plans to double the UK's fleet and to open a second control station at RAF Waddington in late 2012, says Medact, which challenges the legitimacy of what it calls asymmetrical warfare.
Marion Birch, director of Medact and a co-author of the report, said: "Drones are not only unacceptable from a human, moral and legal point of view, they are traumatising families and damaging the chances of peace. We believe it is time for the UK government to stop purchasing, developing and deploying armed drones."