Three al-Jazeera journalists have been arrested on suspicion of illegally flying a drone over key Paris landmarks, the prosecutor’s office has said.

It said the three foreign nationals, aged 70, 54 and 36 were taken into custody on Wednesday afternoon after police spotted the drone flying in the Bois de Boulogne woods in western Paris.

They can be held for a maximum of 24 hours under French law. Flying drones without a license in France is illegal and carries a maximum one-year prison sentence and a €75,000 (£55,000) fine.

Over the past two nights police had received numerous reports from witnesses seeing unmanned aircraft hovering near the Eiffel Tower, the US Embassy and the Louvre museum.

At a time of heightened vigilance in the French capital, after the Charlie Hebdo killings, the sightings had caused nervousness among Parisians.

A Paris prosecutor had called for a police investigation of the drone appearances. Paris prosecutors’ spokeswoman Agnes Thibault-Lecuivre said an unidentified flying object was first seen near the Gare de l’Est train station on Tuesday night, with sightings continuing over the Paris Opera, then on to the Tuileries gardens, past the Eiffel Tower and then south past the Montparnasse Tower.

Police had previously speculated about the motives of those piloting the drones, saying they could be scouts for a sinister criminal operation or part of a benign but ill-conceived prank.

The sightings follow a series of drone-spottings at French atomic plants late last year and, more recently, over the presidential palace and a bay in Brittany that houses nuclear submarines.

An al-Jazeera spokesman said: “Three al-Jazeera English journalists have been held by police in Paris while filming a report on the city’s recent mystery drones. We will comment further when more information is available.”