The Army says nobody was disciplined after a vehicle crashed at a Colorado training range last year, killing one soldier and injuring five.

A spokesman at Fort Carson, where the crash occurred, said Friday the reasons nobody was disciplined were listed in documents held by a separate command.

The Associated Press has requested those documents.

Investigators say a Stryker combat vehicle got lost during a February 2015 exercise at Fort Carson. The vehicle was turning around when it drove over a cliff and rolled 250 feet down a steep slope.

Staff Sgt. Justin Holt, the vehicle commander, was killed. Investigators said Holt suffered shoulder pain and wasn't sleeping well, but a captain cleared him to participate in the exercise against the advice of a physician assistant and a squadron commander.