An American teenager and two other people were killed in avalanche near the Swiss resort of Zermatt, police said Tuesday. One person was flown to a hospital with serious injuries.

The avalanche occurred at about 2 p.m. Monday in an off-piste area of the Riffelberg, above the resort and below the famed Matterhorn peak. Rescuers recovered three bodies and the injured skier, a 20-year-old Swiss man.

The victims were a 15-year-old American boy, as well as a man and a woman whose identification has not yet been concluded, police in Valais canton (state) said in a statement. They gave no further details, but said they currently have no information on the woman’s identity.

Four other people were freed from the avalanche snow, police said.

Prosecutors were investigating the incident.

Heavy snowfall and very strong winds had prompted authorities to warn of a major avalanche risk in the southern Swiss Alps.  

The risk was considered especially high in the Grisons and Valais cantons, both popular ski destinations.  

“Very large, and in some cases extremely large, spontaneous avalanches are to be expected,” the Institute for Snow and Avalanche Research, or SLF, said.

Before Monday, 14 people had died in 12 avalanches and accidents in Switzerland so far this season, the SLF said. Most of the victims have been cross-country skiers.

Last month, five members of a Swiss family were found dead after going missing while cross-country skiing near the Matterhorn in difficult weather conditions. Authorities abandoned the search for a sixth missing person days later.

In a one-week stretch in 2023, six mountaineers fell to their deaths or were killed by rockslides in the same region.

AFP contributed to this report.