By Andrew Porterfield

Drones--unmanned vehicles designed to fly where manned airplanes and helicopters can't go--may be coming to train depots in Germany.

Deutsche Bahn (Germany's national railway) is proposing to test small drones, armed with infra-red cameras, to monitor its larger train depots at night, and get images of any vandals defacing the depots.

While drones are controversial in Europe and elsewhere because of their potential for spying on (and firing weapons at) citizens, the Deutsche Bahn proposal also runs into Germany's strict surveillance laws. Currently, video surveillance is permissible in public places only if the location is considered "dangerous." Deutsche Bahn maintains that since train depots are private property, they would not be considered public places. The railway also says that people outside the depot would not be subject to filming.

Deutsche Bahn estimates that spray painting and other graffiti is costing it almost 8 million Euros a year.

From their humble beginnings nearly three centuries ago as unmanned (but armed) hot air balloons, drone technology has evolved into a sophisticated array of fighting, flying and sighting machines. Some drones are large enough to carry a payload of bombs, while others are tiny enough (and silent enough) to fly into tight spaces and escape detection. Drones have been used for military purposes in the war in Afghanistan, and their use also has been proposed for detecting survivors of natural disasters, as well as for delivering medical supplies to remote areas.

Deutsche Bahn already has surveillance cameras in place at locations like the train depot in Bonn, which was the target of an attempted bombing in December. Since, Interior Minister Hans-Peter Friedrich has called for more surveillance cameras to detect criminal activity. Friedrich has also said that he is working with Deutsche Bahn on enhancing the railway's video surveillance capability.

However, Federal Justice Minister Sabine Leutheusser-Schnarrenberger has warned against diluting Germany's strict surveillance laws, and the GdP police trade union and Green Party have weighed in against increased surveillance.