Chattanooga Ironman bikers begin their course.

Tacks and oil have been thrown on the Chattanooga Ironman bike course, Ironman officials confirmed around noon.

The tacks and oil have caused about thirty flat tires so far, but Ironman staff are working to clean up the mess.

Norm Pingley, an employee of Ironman, said that it's not uncommon for this to happen, especially in rural areas.

Officials have not immediately confirmed where it happened.

This is a developing story. Stay with the Times Free Press for more details.

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