While many wondered whether the phenomenon was linked to some kind of military exercise and others panicked that planes were on fire, the fire balls are believed to have been caused by a meteorite shower.
Social networks lit up at around 6.20pm on Wednesday after hundreds of people caught sight of a fire ball passing through the sky.
"You're never going to believe me but I saw a meteorite, something on fire falling from the sky! "F**king hell I 'm in shock," said one eyewitness.
The regional newspaper Dauphiné Libéré said hundreds of eye-witnesses had contacted them from right across southern France.
Readers described seeing a “green ball with a trail” or a “white ball that exploded followed by a long trail of fire.”
One resident in the Alps told Le Parisien newspaper the meteorite “passed pretty low and horizontally and was a big ball of green fire.”
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