According to Le Dauphine, the group were amateurs and unaccompanied by a mountain guide.
The victims were 56, 55 and 49 years from the La Réunion Island, and had come on holiday to practice mountain sports.
The group had left in the morning from the Conscrits refuge, then to Col des Domes de Miage and finally to Col de la Bérangère (3348 m).
They fall in a crevasse
When they reached the rocky area of Aiguille de la Bérangère, at 3,460 meters above sea level, to the Armancette glacier, they fell 200 meters.
According to France Bleu, one of the mountaineers slipped and fell into a crevasse of the glacier, dragging the other two.
The mountaineers were roped and had about fifteen meters between each other.
All three died during the fall on the steep part of the glacier.
The Chamonix High Mountain Rescue Team opened an investigation to determine the exact circumstances of the accident.
The commander of PGHM, Stéphane Bozon declared "We can assume a technical fault, then an inability of the rope to stop the fall".
"It is illusory to think that one can stop a fall after two meters, by the force of his hands alone. We get ripped off", the commander also said.
The PGHM were called by other mountaineers near the accident, but they could only note the deaths.
We advise mountaineers to be cautious and to hire a Mountain Guide.