A British climber has been killed after a massive chunk of rock fell off Yosemite National Park's El Capitan monolith.
Yosemite park ranger Scott Gediman said that the man was with a British woman who was seriously injured. The pair are not being identified until their relatives are notified.
Mr Gediman said the two were hiking at the bottom of El Capitan's vertical face on their way to scale it when the sheet of rock estimated to be 130ft high and 65ft wide fell.
The rock fall was among seven that happened in the same general area during a four-hour period on Wednesday. Rescuers found no other victims.
The park records about 80 rock falls per year, though they are rarely fatal.
Experienced climbers of El Capitan said they have never seen a rock fall like the one "the size of an apartment building" that plunged down the vertical face.
"I've seen smaller avalanches and smaller falls before where you would just see a tiny dust cloud, this was covering a good portion of the rock in front of us," said John DeGrazio of YExplore Yosemite Adventures, who has led climbers scaling El Capitan for 12 years.
Mr DeGrazio said he had just guided a group to the top of El Capitan when the rock crashed to the ground, sending a large cloud of rock dust into the air. At least 30 climbers were on the wall of the 7,569ft monolith when the huge chunk of rock fell.
"It was more significant than anything I've seen before," Mr DeGrazio said.