A teenager plunged nearly 400 feet to her death at the Grand Canyon, the second such death in three days.

Yuri Nagata of Gufuken, Japan, who would have turned 18 Monday, had moved past a guardrail to descend to a rock ledge Thursday, authorities said."Evidently, a friend suggested taking a photograph of her, and as she was standing up to get the photograph taken, she lost her balance and fell," said Chuck Lundy of the National Park Service.

She was a member of a youth group on a U.S. tour, Lundy said.

On Thursday, a 34-year-old West German woman fell to her death while watching the sunset at a point also on the south rim of the canyon, he said.