The accident happened at Cermis in Trentino province late Friday, RIA Novosti reported.
Four women and four men were crossing a closed trail when the driver lost control of the vehicle, which broke through safety nets and fell about 328 feet down the slope.
Four women and two men died, while two other men were brought to a hospital, official said.
"According to a preliminary investigation report, the accident occurred due to the exceeded speed limit of the snowmobile on a dangerous part of the mountainous road," said Russian Consul General in Milan Alexei Paramonov, adding that an investigation was under way to determine whether a technical failure of the vehicle was a factor.
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