A member of the Dartmouth College ski team collapsed and died over the weekend during a cross-country race, Reuters reported.

School spokesman Justin Anderson said Torin Tucker was climbing uphill on a 25-kilometer course when he fell to the ground and died moments later. Tucker, a 20-year-old junior from Sun Valley, Idaho, did not respond to resuscitation efforts.

"We don't yet know what happened, in part because it was a total surprise," Anderson told Reuters. "There's no reason this should have happened to a phenomenal athlete, a young man who was in great shape."

Dartmouth flew its flags at half-staff Sunday to honor Tucker and the fallen skier's teammates withdrew from the race after his collapse. An autopsy is currently pending family approval but is expected to be performed soon.

"It is with great sadness I write to inform you that we have learned of the death of Torin Tucker '15, who passed away today while competing in a cross country skiing event in Craftsbury, Vt. Torin was there as a member of Dartmouth's Ski Team," the Ivy League school's president Phil Hanlon wrote in a statement, adding that counseling would be available to anyone who needs it. "We have been in contact with his family and share our deepest sympathies with them at this time of heartbreaking loss."

Tucker and the Dartmouth ski team were participating in the 50K event called the Craftsbury Marathon. According to its website, it is the biggest cross-country ski race in the eastern U.S., attracting up to 1,000 racers every year.

"He was one of the most in-shape people I've ever met and I don't know the whole story yet, but it's a tragedy," Jesse Beamish, a fraternity brother and friend of Tucker, told the Valley News. "He was always fun-spirited and in a good mood."