Parts of a mountain glacier collapsed in the Italian Alps on Sunday amid record temperatures, local authorities said, killing at least six people and injuring eight. The Trento provincial government said rescue operations were underway after a large “ice avalanche” involving hikers, adding that there was likely to be a “heavy toll”. The avalanche occurred on Marmolada, which at more than 3,300 meters is the highest mountain in the Dolomites, a mountain range in the eastern Italian Alps that stretches across the regions of Trento and Veneto. The injured were taken to hospitals in the nearby cities of Belluno, Treviso, Trento and Bolzano, Veneto president Luca Zaia said. The huge mass of ice collapsed near Punta Roca, on the route usually used by hikers and climbers to reach the summit, the Alpine rescue unit said. “Fortunately the weather conditions are good, but the risk is that there could be further collapses,” a spokesman said. Helicopters and dogs were used to find survivors. An early summer heat wave in Italy saw temperatures in Marmolada reach 10 degrees on Saturday, Zaia said. Rising average temperatures have caused Marmolada Glacier, like many others around the world, to shrink steadily over the past few decades. The Morning Update and Afternoon Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.