At least five drones were spotted in the skies over Paris in the early hours of Tuesday, causing police to launch an investigation into the latest of a string of similar sightings over sensitive French sites.
Security concerns have been raised over the repeated appearance of unidentified drones, which in the last few months have been seen overflying nuclear power stations and the presidential palace.
In the latest case, drones were sighted by the police in the Parisian sky between 1am and 6am on Tuesday morning, flying near six French landmarks: the Eiffel Tower, the military museum at Les Invalides, Place de la Concorde, the Bastille, the US Embassy, and the Montparnasse Tower — the capital's tallest skyscraper.
A police spokesman quoted by the Daily Telegraph said that "it might be a coordinated action, but we don't know yet."
This is the first time that so many drones have spotted on one night. The drones' pilots are still on the run and the police are actively looking for them as drone overflights are forbidden in French cities.
The first drone was spotted at around 1am, around 330 feet (100 meters) above the US Embassy, located yards away from the Place de la Concorde, another sensitive site which was also overflown by a drone. Another was seen on the other side of the Seine near the Eiffel Tower and the Invalides military museum, both located in the seventh arrondissement of the French capital. One last drone apparently flew around the Bastille neighborhood located in east of the city.
It is possible, due to the proximity of the sites, that there could be less drones than reported by police, and that some of overflights may have been made by the same craft.
The national gendarme service announced on Tuesday that an investigation has been launched, which will be led the Air Transport Gendarmarie. "A dozen investigators specialized in aeronautics are currently recovering testimonies," a police source told French newspaper 20 Minutes.
The drones spotted last night were fairly small and of a type that is widely available. According to the police, this type of drone cannot do any damage if crashed as they are too light. Yet some fear terrorists could use drones to carry explosives or to spot places for future attacks.
Christophe Naudin, a criminologist and an expert in aviation security, told the Telegraph: "The aim of these flights may simply be to demonstrate that the authorities are incapable of responding to these threats, which could become real in a few years,"
Not only are drone flights banned over urban areas in France, it is also punishable by law to fly a drone at night anywhere in the country. Sanctions can include a fine of up to 75,000 euro ($85,000) and a one-year prison term.
The sightings have received substantial attention in the French media, as it is not the first time drones have been sighted over sensitive sites.
A month ago, on January 20, a drone was seen above the French presidential palace, the Élysée, creating an outcry over security days after the Paris attacks on Charlie Hebdo and a kosher supermarket.
Naudin said the operation appeared to be "well-organized" and that the type of drone involved was generally used by professional filmmakers rather than amateur enthusiasts.
The first drone sighting came on October 5, flying over the Superphénix nuclear power plant in southeast France. French power giant EDF has filed a complaint with the police, but maintains that these flyovers are "without consequence for the safety or operation of these installations."
The source of the drone activity remains unclear. Speculation initially turned to Greenpeace, whose activists have in the past staged interventions at nuclear sites throughout France, including one in 2012, during which the group flew over the Bugey plant in a powered hand-glider to highlight the lack of security.
However, Greenpeace later denied any involvement in the piloting of these mysterious drones. Naudin said that he thought a more "extreme" organization was likely responsible, suggesting that an "eco-terrorist" group could be behind both cases.
According to The Wall Street Journal, an official at the US embassy declined to comment on the drone flights.
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Main image via Flickr