Police in southern California are investigating the circumstances that led to the hospitalization of nearly 30 runners who participated in the Santa Barbara Half Marathon on Sunday.
Santa Barbara police said in a statement to the Associated Press that they had opened an investigation after receiving reports from Santa Barbara Cottage Hospital about multiple half-marathon participants seeking medical treatment for "unusual symptoms".
Cottage Health stated it recorded a "larger than expected number of emergency visits … a number of them with similar symptoms of undetermined cause". As of Monday, 27 participants had visited emergency rooms in Santa Barbara and Goleta, a city approximately 10 miles west.
Of those who sought care either through hospital transport or self-arrival, 24 were treated and discharged by Monday morning. Three others remained in stable condition according to the hospital's update to the Associated Press.
The race organizers reported that they transported 15 individuals from on-site medical tents to local hospitals. Event director David Monico said their medical team provided treatment for dehydration and overheating both during the course and at the finish line.
Monico told The Guardian that "there is no additional information to suggest that the issues some of the participants experienced were caused by anything other than endurance event exertion-related symptoms".
The half-marathon spans about 13 miles, with over 4,640 people participating. On Sunday, temperatures reached a high of 88F (31.1C), which officials described as unusually elevated for November in the region.