COLUMBUS, Ind. — Saturday morning’s temperatures warmed up enough by 9:50 a.m. that Mill Race Marathon officials issued a red-flag warning, indicating a high risk for runners.

The warning asks runners to be aware that heat illness is possible. The warning advises runners to slow down and take their time.

Runners compete in the 5th annual Mill Race Marathon in Columbus, IN. Saturday 9/23/17 Jamie Tomlinson | for The Republic
Runners compete in the 5th annual Mill Race Marathon in Columbus, IN. Saturday 9/23/17 Jamie Tomlinson | for The Republic

The morning temperature by that time had risen to 76 degrees — about 12 degrees higher than at the 7:30 a.m. start of the races. The day’s afternoon high was expected to reach 90 degrees, after the races were over.

Because of the projected hot weather and risk for heat-related injuries, race organizers sent a letter to participants in the three races that encouraged marathon runners estimated to finish beyond four hours to consider only going half the distance instead.

Within the first two hours, the marathon’s medical tent was starting to treat an increasing number of runners for heat-telated matters, medical director Jennifer Hoskins said. While the initial medical reports were mostly for cramping, matters got more serious as the morning progressed and the temperatures rose. One male runner was seen receiving an IV, with wet towels placed on his body.

At 10:15 a.m., one woman had to be transported to Columbus Regional Hospital because of a heat-related issue, and more runners were seeking help for overheating, Hoskins said.

Ten minutes later, a man was being submerged in a cooler of cold water by the marathon medical staff after he passed out while seeking help at the medical tent.

WINNERS: The top male finisher in the 5K was Matt Newell, a Northside Middle School student from Columbus, and the top female 5K finisher was Jordan Callison of Bloomington, Indiana. In the half marathon, the top male winner was Jared Campbell of Franklin, Indiana, and the top female winner was Rachael Brewer of Tuscola, Illinois. The top male winner in the full marathon was Peter Kosgei of Grand Rapids, Michigan; and Lauren Jackson of Augusta, New Jersey, was the top female winner.

This story will be updated.

Charlie and Jayne Farber have fun in the 5th annual Mill Race Marathon in Columbus, IN. Saturday 9/23/17 Jamie Tomlinson | for The Republic
Charlie and Jayne Farber have fun in the 5th annual Mill Race Marathon in Columbus, IN. Saturday 9/23/17 Jamie Tomlinson | for The Republic
Patty Brumberg of Scipio was all smiles after finishing her first official 5K run, with son Henry there for encouragement. Photo by Kirk Johannesen
Patty Brumberg of Scipio was all smiles after finishing her first official 5K run, with son Henry there for encouragement. Photo by Kirk Johannesen
Melissa Hinckfoot and Leah Hinckfoot hold a sign for Sarah Weber at mile 4 of the half marathon. Photo by Julie McClure.
Melissa Hinckfoot and Leah Hinckfoot hold a sign for Sarah Weber at mile 4 of the half marathon. Photo by Julie McClure.
Zane Moravec, 12, left, and Ethan Lax, 13, students at St. Bartholomew Catholic School, are photographed after finishing the 5K. Photo by Kirk Johannesen.
Zane Moravec, 12, left, and Ethan Lax, 13, students at St. Bartholomew Catholic School, are photographed after finishing the 5K. Photo by Kirk Johannesen.