Published: Jul 28, 2013 10:24 AM EDT

INDIANAPOLIS (AP) - The brakes on the bus carrying teenagers home from a youth camp in northern Michigan failed as the vehicle exited the Indianapolis interstate, causing it to strike a retaining wall and flip on its side, according to a newspaper report Sunday.
    
Bus driver Dennis Mauer, 68, told the Indianapolis Metropolitan Police that the brakes failed and he wasn't able to keep the bus from crashing Saturday afternoon, the Indianapolis Star reported (http://indy.st/18KMasD ). Three people died and several were injured.
    
The investigation into the crash, which happened on an Interstate 465 exit ramp, is ongoing, authorities said. Indianapolis Fire Department Lt. Ato McTush said Saturday that investigators had not determined whether the church-owned bus had mechanical issues.
    
The bus was nearly finished with a 365-mile journey, overturning just a mile from the Colonial Hills Baptist Church. At the church, parents were waiting to pick up their children after a weeklong camp filled with prayer, zip lines and basketball when a bus carrying younger campers pulled in, its passengers screaming.
    
Jeff Leffew, 44, of Fishers, had sent four daughters to Camp CoBeAc, near Prudenville, Mich. Only one daughter was on the bus that pulled into the parking lot, and he raced to the crash site in northern Indianapolis. What he found was a surreal scene, with clothing and other items strewn about and windows missing from the bus.
    
"You're just praying that it's not as bad as it looks," said Leffew, a deacon at the church.
    
His daughters escaped with just bumps and bruises, but others weren't as fortunate. Indianapolis fire officials said a husband and wife were dead at the scene, along with a third person whose age they didn't describe. Twenty-six people were taken to area hospitals, and one teenager remained in critical condition on Sunday.
    
Indianapolis Public Safety Director Troy Riggs called the crash a "great tragedy."
    
"They were not that far from home. ... That only adds to the tragedy," Riggs said at the crash scene. He said there was no indication that the driver had a medical emergency.
    
Witnesses described a horrifying scene.
    
Duane Lloyd told WTHR that he heard a loud noise behind him as he was traveling near the intersection and saw the crash around 4:15 p.m. - about the time youth pastor Chad Phelps had tweeted that the group would arrive at the church.
    
"I heard a skid. I looked back. I see this bus in the air and people falling out of the bus," Lloyd said. "I could have gone my whole life without seeing that."
    
He said people approached and tried to help.
    
"People were literally trying to lift the bus," Lloyd said. "You just try to do what you can do."
    
Sasha Sample, 28, told The Indianapolis Star some victims were lying in the road, while others were able to limp to the side.
    
"Everybody had boils and scrapes on them," she said. "People were trying to climb from under the bus."
    
Sample, a nurse, said she borrowed a belt to make a tourniquet for the bus driver's arm but wasn't able to help the man next to him, who was already dead.
    
"I couldn't do anything for him," Sample said. "So you triage. You help those you can."
    
Fire officials said 37 people were on the bus, and the injured included children and adults. Three teenagers were still at IU Health Methodist Hospital, spokeswoman Sally Winter said Sunday, including one in critical condition. Five teenagers remained at the Riley Hospital for Children at IU Health; a toddler had been treated and released.
    
Many of the patients had head, arm and leg injuries, fire officials said.
    
Families of the bus passengers gathered at the church Saturday evening to comfort each other and pray.
    
Mayor Greg Ballard described many as "remarkably positive" despite their sorrow, but said there will be difficult days ahead.
    
"Some of the teenagers are hurting pretty bad and you can see that in their faces," he said.
    
Bob Taylor, who retired as the church's pastor four years ago, said members of the congregation would come together Sunday and take comfort in their faith.
    
"Our church family will meet tomorrow and pray together and sing songs together and just trust the Lord to give his grace," he said.
    
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Associated Press reporter Tom Murphy contributed to this story.

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