Trento prosecutor Sandro Raimondi said in an interview on Italian state radio on Wednesday that he had opened a formal investigation to determine whether there was negligence. The public prosecutor wants to consult geologists.
But Raimondi said that at the time it looked like the avalanche could not have been foreseen.
“The unpredictability of that moment is the main character,” he said.
Forensic police investigators dispatched from the city of Parma took samples of some of the recovered remains on Wednesday to determine if they belonged to any of the missing persons.
Meanwhile, the mayors of Canazei and smaller towns at the foot of the mountains in the Dolomite chain issued ordinances closing the Marmolada peak to hikers. Some people ignored the orders and climbed the lower slopes.
Authorities have cited a week-long heatwave in northern Italy and scant winter snowfalls as likely factors behind the weekend’s collapse of the glacier, which has shrunk dramatically over decades.
Last weekend the temperature on the Marmolada exceeded 10 degrees Celsius (50 F), unusually high for early summer, authorities said.
Polar science experts at a research center run by the Italian government estimated that the Marmolada glacier could disappear completely in the next 25 to 30 years if current climate trends continue.
Between 2004 and 2015, the glacier lost 30% of its volume and 22% of its area.
People whose livelihoods are linked to the mountain offered their own observations. Carlo Budel, hut manager on the Marmolada side, recalled that last month the glacier was not covered with snow.
“Last year when I moved into the cabin on June 1, it only took me half a day to get in because the cabin was completely covered with snow,” he said. “But this year I opened the main door in just 30 minutes.”
Andrea Rosa and Paolo Santalucia contributed to this report.
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