Extreme athlete Dean Potter, renowned for his bold and sometimes rogue climbs and Base jumps, was one of two men killed while attempting a wingsuit flight in Yosemite National Park, a park spokesman said.
Someone called for help late on Saturday after losing contact with Potter, 43, and his climbing partner, Graham Hunt, 29. They had jumped from a 2,300-metre promontory called Taft Point, park ranger Scott Gediman said on Sunday.
He said a search-and-rescue team looked for the men overnight but couldn't find them. On Sunday morning, a helicopter crew spotted their bodies in Yosemite Valley. No parachutes had been deployed.
Base jumping is an acronym for fixed objects in which someone can parachute from: building, antenna, span, and earth (such as a cliff). The sport is illegal in all national parks, and it was possible the men jumped at dusk or at night to avoid being caught by park rangers.
Potter and Hunt, who lived near Yosemite, were prominent figures in the park's climbing community, Gediman said.
"This is a horrible incident, and our deepest sympathies go out to their friends and family," Gediman said. "This is a huge loss for all of us."