Two mountaineers -- one French and the other Dutch -- died in a rockslide while climbing the Aiguille du Tour on the Swiss side of the Mont-Blanc range, police said Tuesday.

A 22-year-old climber, also from the Netherlands, was injured in Monday's accident, regional police of the canton of Valais said.

The 26-year-old Frenchman and the Dutch climber, who was 10 years older, were climbing in two separate rope groups when a slab of rock broke off near the summit overlooking the Trient glacier.

It hit a rope, killing one of the climbers attached while injuring another. The rock then hit a second rope killing a second mountaineer, police said.

The 3,540-metre (11,614-foot) Aiguille du Tour, on the border with France, has two summits of equal height at a distance of around 130 metres.

Crossing the south and north of the mountain's summits is a popular high-altitude feat for climbers.