One pilot was killed and another injured when they ejected from a U-2 spy plane shortly before it crashed in Northern California, the US Air Force has said.
Military officials said the aircraft crashed shortly after taking off from Beale Air Force Base on a training mission around 9am local time on Tuesday.
The Air Force did not release the pilots' names or any information about the condition of the surviving airman.
The aircraft was assigned to the 1st Reconnaissance squadron. It crashed in the Sutter Buttes, a mountain range about 60 miles north of Sacramento.
The U-2 is a surveillance and reconnaissance plane capable of flying at extremely high altitudes.
It gathers imagery and electronic signals for intelligence analysts and battlefield commanders.