One person engulfed in an avalanche in the Swiss Alps has died, police said Wednesday, as rescue operations to find other possible victims were paused after an all-night search. 

Four people had been reported as injured in the avalanche on Tuesday at the Crans-Montana ski station in southern Switzerland.

One of the wounded, a 34-year-old French national, has died, police in Valais canton said in a tweet. 

"Searches that continued through the night have been stopped. They will resume if the situation requires," police added. No new victims were discovered overnight.

The avalanche hit during the early afternoon on a slope 2,600 metres up at Crans-Montana, which was busy with skiers during school holidays.

Swiss media said search efforts for the victims included sniffer dogs, four military helicopters and up to 250 rescue workers. 

The avalanche was unusual in that it hit a designated ski slope, while the vast majority of deadly avalanches in the Alpine nation hit people skiing off-piste.