Three people have been killed and three others injured in a helicopter crash in the Swiss Alps. The collision occurred at the Petit Combin Mountain airfield at approximately 9.25am local time on April 2, after the helicopter escorting skiers to a mountain drop-off point slipped off the summit. The group comprised of four tourists, a mountain guide and the pilot. A 15-year-old American teenager was among one of the three fatalities, alongside a man and woman whose identities have yet to be confirmed. A 20-year-old Swiss man was flown to hospital with serious injuries after the helicopter slippe…