INDIANAPOLIS (AP) -- Members of an Indianapolis church are grieving and investigators are seeking to determine what caused a bus carrying teenagers back from a church camp to crash a mile from its destination.

Three people died and dozens more were injured.

The bus carrying 37 members of the Colonial Hills Baptist Church crashed Saturday at the end of a six-hour journey from northern Michigan.

Witnesses say the bus as it came speeding off Interstate 465, slammed into a retaining wall and overturned. Some victims were flung from the bus and others were trapped inside.

Indianapolis Fire Department Lt. Ato McTush says investigators haven't immediately determined a cause for the crash. WTHR-TV reports the driver told witnesses his brakes failed.

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