An Austrian man was severely burned when he was struck by lightning this week while hiking in a remote wilderness area in the Sierra Nevada, authorities said.
The hiker, whose identity was not released, and his girlfriend were visiting from Austria and had set out to hike with a friend Tuesday afternoon, according to the California Highway Patrol's air operations in Sacramento.
As the friends hiked from Donner Summit to Squaw Valley, they observed no thunderstorm activity or lightning, the CHP said on Facebook.
The victim then separated from the group and started walking ahead.
That's when his girlfriend and friend "heard a large crack and saw a flash of light" at Tinker Knob summit, where the victim had been standing, the CHP said.
"Worried about subsequent strikes, the two friends remained off the ridge and called 911 for help," the CHP said. "They attempted to make voice contact from a safe distance with the victim."
The man eventually yelled back and waved his arms.
A CHP helicopter later responded and landed at the summit, where a paramedic assisted the victim, who had difficulty walking, authorities said.
The victim was taken to an area hospital, where he was stabilized. He was later flown to the UC Davis Burn Center, the CHP said.
Photographs from the scene showed the victim's tattered clothing and mangled shoes.