A Czech mountaineer died in an accident on Tuesday on the Lyskamm mountain near Zermatt, in canton Valais. The 34-year-old was the victim of a rockfall at an altitude of around 4,300 metres. The accident happened at around 9am on the north face of the Lyskamm, Valais cantonal police said on Wednesday. Two climbers were on a high-altitude expedition when a rockfall was triggered, striking one of them. His companion alerted the emergency services, who were dispatched in an Air Zermatt helicopter.