ST. LOUIS, MO. (KMOX) – Not everybody got to finish the St. Louis marathon foot race Sunday and the heat was to blame. 

Despite an early start for the race, runners began to collapse in the heat. 

Event organizers called for extra ambulances and arranged for trucks carrying water bottles to patrol the route. 

Then, at about 9.15, the decision was made to redirect runners who had not reached the 9-mile mark to a shorter course. 

The “GO! St. Louis” marathon attracts about 20-thousand runners each year. 

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