Mountain guides in the Italian Alps are warning that when the snow melts there this spring they may find bodies of migrants who have been attempting to make the treacherous land crossing from Italy into France.
The tightening of border controls between France and Italy in recent years has prompted some migrants -- often teenagers -- to abandon coastal routes, in favor of a perilous two-kilometer trek through the southern Alps, the same slopes visited by skiers enjoying winter vacations.
Up to 70 mostly African migrants each week are crossing the Col de l'-chelle mountain pass on their trek northward into Europe, having already traveled through Libya and across the Mediterranean. Guides say it is as yet unclear how many have died while trying to make the trip.
"The reason we go out and look for migrants is because we want to avoid finding bodies when the snow melts. We can't exclude that this has already happened," a mountain guide who asked not to be named (as he's worried about getting in trouble with the law) told CNN.
"Only in the spring will we know what's under the snow and if there are bodies they could be found by us but they could also be found by tourists," he said.
Volunteer rescuer Simone Bobbio told CNN he has spent more time so far this winter rescuing migrants than skiers.
Bobbio said the migrants are unfamiliar with and poorly equipped for the freezing conditions (dropping as low as -20 degrees Celsius), recalling one man who set off under snowfall during the night and had to be rescued after losing his shoes and suffering frostbite on his feet.
"These people are not well equipped, they don't have experience so often they need to be rescued," Bobbio told CNN.
"Our volunteers have had a lot more work but until now they are dealing with it quite well."
One migrant, 28-year-old Mamadou Ba, from Mali, made the crossing 18 months ago, but told CNN he regretted it.
Once at the top, Ba and the Guinean migrant he was traveling with got stuck inside a hole. The two men spent the night crying, believing that they would die there, he said.
Eventually, Ba managed to get out of the hole and headed down the French side of the mountain to raise the alarm. His Guinean friend was rescued an hour later and had his hands amputated due to frostbite.
Ba had made it to France, but he had to have nine operations and lost both of his feet. He's now living in Briancon where he goes to the hospital once a week and is still learning how to walk.
"I had a beautiful life before and now my life is destroyed," Ba, who left Mali over seven years ago, told CNN. He said he hopes to find a job that allows him to work while sitting down.
"Everything I did before I can no longer do. I used to play football. I used to love hip-hop dancing," he added.
Asked what advice he would give migrants attempting the climb, Ba said he would urge them to turn around.
"They've never seen snow, they don't know. If you tell someone in Africa that snow is dangerous, he'll tell you you're lying because he thinks snow is fun," Ba said. "I had no idea snow could burn."
Back on the mountain, Bobbio tried to dissuade a group of West African teenagers from making the trek.
One of the migrants, who did not wish to be named, said he was fleeing countries where he had faced hostility and racism.
Italy was the eighth county he had fled since leaving his homeland, and this was his second attempt getting over the Col de l'-chelle, he said.
Several hours after watching them start their climb, we were told the group had turned around because of difficult conditions at the top.
But they'll likely try again, as Wayne, one of the migrants, told CNN before he started the climb.
"It's the second time we're trying to cross," he said. "We'll try as many times as possible until we get where we need to be."