Two base jumpers, including an Australian, were killed in separate accidents in the French Alps on Sunday (local time) after parachuting off mountains in their wingsuits. Their deaths bring to four the number of people killed taking part in the extreme sport in France this month. ... On August 6, two base jumpers, one from Switzerland, the other from France, died in similar accidents in the Alps and French Pyrenees. ... Unlike skydiving, which involves leaping from an aircraft, base jumpers take off with a parachute from a fixed point, usually a cliff or a bridge. The sport carries high...