(NECN/NBC: Dan Scheneman) - A bus carrying 37 teens and adults was returning from a summer camp when it crashed while exiting an Indianapolis interstate on Saturday.
The crash killed three people and sent 28 to local hospitals for treatment.
The bus was only a mile from its destination, a local church, when the crash happened.
Witness Duane Lloyd was in front of the accident but said the sound of it all caught his attention.
"I hear the impact, and then I realize something went behind me. And I stopped and I see this bus in the air, and people falling out of this bus," he said. "I could've gone my whole life without seeing that."
According to witnesses, the bus veered across the road, flipping onto the median before skidding to a stop.
"I did hear the bus driver say - I asked him, 'Can I get you something?' And he said, 'My brakes just failed, my brakes just went out,'" Lloyd added.
Numerous travelers stopped at the scene to help the victims.
Families and members of the church's congregation gathered at the bus's destination seeking and giving comfort.
"It's difficult to overstate the amount of faith that's in there right now. It's a strong church, and they're just trying to help each other right now," said Indianapolis Mayor Greg Ballard.
As for the investigation, officials said they planned a thorough look into what caused the accident.
"They'll look at everything bumper to bumper to see if everything was in proper working order. They'll talk to all the he witnesses. It will be a thorough investigation and it will take some time," said Indianapolis Public Safety Director Tony Riggs.
Watch the attached video for more.