Police in the canton of Valais said the 42-year-old woman died two days after being hospitalised.

Police in the canton of Bern said separately on Monday that the bodies of two Swiss climbers were also found further east in the Swiss Alps.

All of the dead skiers, who included two couples, were Italian, except for a Bulgarian woman who died Tuesday.

A police spokesman said a Swiss man aged 72 and a Frenchwoman aged 56 remained in a serious condition.

The group were forced to spend the night exposed to the elements at altitude after poor conditions caught them by surprise Sunday in the Pigne d’Arolla region of the Swiss Alps as they trekked along a route called The Serpentine.

The manager of a rest stop in the remote mountain region sent out a call for help at dawn on Monday, triggering a major relief operation that involved seven helicopters, police said. Fellow skiers reported them missing to authorities, who raised the alarm.

In the case of the Swiss climbers, the alert was sounded late on Sunday but the bad weather foiled rescue efforts.