A participant in the Cocodona 250 ultramarathon in Arizona has died after experiencing a medical emergency, race organisers confirmed on Tuesday.
In a statement posted on Instagram, organisers said the runner suffered a “serious medical emergency” during the 253-mile (407km) endurance event, which began on Monday and is scheduled to finish on Saturday. They added: “Out of respect for the runner’s family and loved ones, we are not sharing additional personal details at this time.”
The race, organised by Aravaipa Running, has been held annually since 2021 and covers a route from Black Canyon City, about 20 miles north of Phoenix, to Flagstaff. The course links some of Arizona’s most iconic trails and towns, beginning in the desert and featuring an estimated 38,791ft (11,823m) of elevation gain, with a high point of 9,241ft (2,817m) outside Flagstaff.
Organisers said the race would continue in the runner’s honour, asking participants and crew “to carry the memory of this runner with you on the trail”. The race tracker listed nearly 400 participants. Last year’s winner, American Dan Green, set a course record of 58 hours 47 minutes 18 seconds, while American Rachel Entrekin was the top female finisher in 63:50:55.
Entrekin led this year’s race through 48 hours, according to Run by Outside, and is attempting to become the first woman to finish first overall. The incident follows a 2025 death of a runner during a 102-mile race in Colorado and a 2021 tragedy in China where 21 competitors died during a 62-mile ultramarathon amid freezing conditions, raising ongoing safety concerns in the sport.
