'I just can't believe that I saw it happen,' said Elizabeth Collins, who was sitting next to her friend when she shot the end of the race with her camera.
'There was this loud crash and all of the sudden, I realized there was flying debris going over our heads and we just ducked.'
The debris included a large section of the safety fence and pieces of the car that slammed into it.
Eleven-year-old Gabe Hartman recorded the accident from a different angle that occurred when one car clipped another one.
'So I ducked for cover not knowing what it was,' said Hartman. 'And so my friends and I were basically showered with small pieces of debris.'
Most of the injuries were minor but two spectators, an official and IndyCar driver Dario Franchitti were taken to the hospital. All of them were treated and released except for Franchitti, who remains there in fair condition.
IndyCar officials have promised to thoroughly review the incident in an effort to reduce the risks of racing.
Some fans said they were well aware of the dangers because of the crash on Sunday.