Four skiers were confirmed dead and five others were in critical condition after having had to spend the night exposed to the elements of the Swiss Alps, police said overnight.
Bad weather in Pigne The Arolla area Swiss Alps Sunday local time caught a group of 14 skiers surprised, the police in the Wallis Canton said in a statement.
The head of a rest period in remote mountain region issued a call for daylight help at Monday local time triggering a major relief operation involving seven helicopters, police said.
"Four people lost their lives, five others are in a critical state," said the statement.
The police showed that one of them killed "likely" died after a fall and was found dead on the spot while three others died later in the hospital.
Some of those not described as being in critical condition suffer from "mild hypothermia" but their "life is not in danger" according to the police.  The skiers were Italian, French and German citizens, said the police and added that efforts were made to formally identify them and contact their families.
The group had set out from the Dix stop and intended to make it vignettes to sleep, trekking along a route called serpentine.
The fatal accident was the latest in a series that affects skiers in Switzerland in recent weeks.
German retailer Karl-Erivan Haub was missing after skiing solo in Swiss Alps earlier this month.
The German 58-year-old head of Germany's exciting Tengelmann retail group has not yet been found, but the authorities have expressed hope to discover him alive.
Haub apparently resigned from an elevator at Klein Matterhorn. Separately, three Spanish cross-countrysleders died after being hit by an avalanche that hit the Fiescheralp area in the Swiss Alps on 31 March.