A series of cable cars became stuck over the Mont Blanc range in the Alps, trapping 110 people who are being evacuated by helicopter, French officials have said.
Chamonix mayor Eric Fournier said "there's nothing fundamentally to fear".
Mr Fournier, who spoke to BFM-TV, said Italian authorities are helping with the rescue.
It is not clear what caused the cable cars to stop - or if there was an electricity outage.
The 110 people got trapped in "late afternoon" in the panoramic Vallee Blanche Cable Car that rises to an altitude of 3,778 metres (12,395ft), a local police official said.
It connects the famed Aiguille du Midi peak to the Pointe Helbronner and takes 30-35 minutes.
The cable cars on the Mont Blanc range offer spectacular close-up views of Western Europe's tallest mountains, glaciers and steep valleys deep below.
The Vallee Blanche Cable Car is operated in the summer season, when large numbers of climbers and tourists converge on the area.
Another series of cable cars takes skiers and visitors to the peak of the Aiguille du Midi year-round.