Italian alpine rescue officials announced that 5 people were killed in a midair collision between a tourist airplane and a helicopter transporting skiers to a glacier in the northwest region of Val d’Aosta.

According to Alpine rescue corps spokesman Walter Milan, the accident happened at an altitude of around 9.843 feet (3,000 meters) over Rutor glacier Friday afternoon, January 25. One person is in a hospital with serious injuries.

The dynamics of the crash remains unclear as rescue crews worked to remove all of the bodies. The nationalities and identities of the victims have not been released.

Rutor glacier covers 9 square kilometres (3.5 square miles) and is the 2nd-largest in Val d’Aosta region, which borders France. Skiers frequently access it via helicopter during winter.