The Valais canton (state) police were notified of the incident in the Grand-Combin massif just after 6 a.m. Seven rescue helicopters were called in.
Seventeen climbers were there in various groups when the ice chunks broke off at a height of 3,400 metres (11,150 feet). Two persons died at the scene: a 40-year-old French woman and a 65-year-old Spanish man.
According to police, nine more persons were transported to hospitals in Sion and Lausanne, with two of them critically injured. Other climbers were helicoptered out.