INDIANAPOLIS - Officials said it'll be at least a week before the cause of the Saturday's fatal bus crash is determined.
Investigators were studying the actual physical pieces of the bus Monday.
The driver of the 1986 Prevost bus told police that his brakes failed as he exited the highway, causing the bus to strike a median and overturn.
The church that owned the bus said it was properly maintained and inspected.
The Call 6 Investigators learned that the specific type of bus was required to undergo an annual inspection that involves a review of 13 key mechanical areas including the brake system.
The paperwork is not filed with any agency, but is required to be on board if the bus is pulled over.
Three people -- a married couple and a mother of five -- were killed in the crash.
The most seriously injured survivor of the Indianapolis bus crash that killed three people has been moved out of an intensive care unit.
An Indiana University Health spokeswoman says the teenager who was in the Methodist Hospital ICU in critical condition is now listed in good condition.
Two additional teens remained at Riley Hospital for Children after Saturday's crash. The patients were listed in good condition. Three other teens were released Monday from Riley and Methodist.
Officials said two patients remained at St. Vincent Hospital.
They were among 37 people from Colonial Hills Baptist Church of Indianapolis whose bus overturned at an Interstate 465 exit ramp while returning from a Michigan camp.
The crash killed the church's youth pastor, his pregnant wife and a camper's mother.
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