The death toll rose to nine Wednesday from a glacier avalanche Sunday in the Italian Dolomite Mountains, Maurizio Fugatti, president of the province of Trento, said as rescue workers continued to search for victims.

The two new casualties were spotted by drones on Wednesday near the edge of the avalanche’s debris field, officials said.

Five hikers believed to have been near the avalanche remain missing.

Precarious conditions on the mountain are preventing search and rescue teams from working near the site of the avalanche.

A police team adept at DNA analysis has also been called in to assist with identifying the victims.

The avalanche occurred when a piece of glacier the size of an apartment building broke free from the Marmolada mountain, which stands some 3,300 meters high.

A large part of the country is experiencing a heatwave, and scientists say climate change is putting more glaciers at risk of breaking off from the mountains.

Some information in this report comes from The Associated Press and Reuters.