WASHINGTON—The U.S. Army said Wednesday that there is no evidence that Sgt. Bowe Bergdahl engaged in any misconduct during his five years in captivity.

Sgt. Bergdahl is the focus of a continuing Army investigation trying to determine whether he attempted to desert his unit on June 30, 2009 while stationed at a small U.S. outpost in eastern Afghanistan. If charged with desertion, Sgt. Bergdahl could face court-martial, prison time and, in the most extreme sentence, the death penalty.

The Army investigation was launched after some soldiers who served with Sgt. Bergdahl accused him of deserting. A classified 2009 investigation concluded that Sgt. Bergdahl voluntarily left the outpost, but stopped short of characterizing his intentions because the Army wasn't able to talk to the soldier while he was held by Afghan insurgents, according to officials familiar with the findings.

Some soldiers who served with Sgt. Bergdahl speculated that he had helped his captors while being held, but Army officials said Wednesday that there is no indication that he did so. "We have no reason to believe that he engaged in any misconduct" during the five years he was held captive, said one Army official.

Sgt. Bergdahl has told the military team helping him recover that life in captivity was often difficult and that he was confined to a cage for part of that time, officials said.