A 24-year-old mountain biker was struck and killed by lightning Sunday on a trail in southwest Colorado.

The San Miguel County Sheriff’s Office identified the victim John Daniel Huisjen of Durango. His relatives have been notified, officials say.

According to sheriff’s spokeswoman Susan Lilly, Huisjen and his girlfriend were riding on the East Fork Trail near the Lizard Head Wilderness about 17 miles southwest of Telluride when a storm rolled in just before noon. The couple were part of several groups of mountain bikers who took shelter below tree line in the area when he was struck by lightning.

24yom mtn biker struck & killed by lightening strike E. Fork Traill near Telluride. Deputies, EMS, SAR, attempted life saving efforts. More. pic.twitter.com/CB4jonSfri — San Miguel Sheriff (@SheriffAlert) August 13, 2017

Huisjen’s girlfriend ran down the trail to get help, Lilly said, happening upon an off-duty county emergency medical technician. That EMT sent a friend down the trail to find a cellphone signal and call for help before attempting to resuscitate the unresponsive Huisjen, Lilly said. Bystanders had performed CPR.

Emergency response and rescue workers from San Miguel County responded and hiked a half mile up the trail to reach Huisjen but could not revive him. Related Articles September 8, 2020 What is gravel biking and why is it so popular in Colorado?

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Huisjen’s girlfriend had injuries that were not considered life-threatening, according the sheriff’s office.

“This is a horrible tragedy,” Sheriff Bill Masters said. “Our thoughts are with his family.”

Masters credited first responders and bystanders for doing all they could to help Huisjen.