 -- An investigating officer described Sgt. Bowe Bergdahl as remorseful at a hearing today regarding Bergdahl's disappearance.

"I believe he is remorseful," Major Gen. Kenneth Dahl said, also calling Bergdahl "young, naive and inexperienced." He also said Bergdahl expressed that he hoped no fellow officers were hurt.

The 22-person investigative team spent 59 days investigating Bergdahl, Dahl said, noting that Bergdahl was not obligated to talk with him, but he did.

Dahl said he believes Bergdahl departed his outpost on June 29, between 10 p.m. and midnight, and encountered the Taliban between 8 a.m. and 10 a.m. When the Taliban encountered him, “They beat him up a bit," Dahl said, adding that Bergdahl tried to run away on the first day after he was captured.

"I do not believe that there is a jail sentence at the end of this process," Dahl said. "I think it would be inappropriate."

No soldiers died during the recovery mission, Dahl said.

Dahl also described Bergdahl as challenged by interpersonal relationships and said he had unrealistic expectations of other people. Dahl added that he doesn't believe Bergdahl had a mental health issue when he joined the Army.

The hearing at Fort Sam Houston in San Antonio will determine whether Bergdahl should face a military tribunal for leaving his post in Afghanistan in 2009, which military officials said led to his being captured by the Taliban. Bergdahl was returned to the U.S. as part of a prisoner exchange with the Taliban in 2014.

Today was the second day of the hearing.

Bergdahl has been charged with desertion and misbehavior before the enemy. Should the case be referred to a court martial, he could face a maximum penalty of life in prison if convicted.

Bergdahl will not testify, his attorney, Eugene Fidell, said today before the hearing began. Fidell said the sworn statement his client gave military investigators last year has everything relevant he has to say about his situation.

When Bergdahl's former squad leader testified today, he discussed his demeanor during his deployment to Afghanistan, describing him as "introverted" and "quiet."

Bergdahl was a good soldier, former Army Sgt. Greg Leatherman said at the hearing, but Bergdahl wasn't adjusting well to deployment and didn't want to interact with fellow soldiers.

Leatherman told his first sergeant that Bergdahl should talk to someone, but added that there was a stigma attached to asking for help.

"It's going to be taken as a sign of weakness," Leatherman said of the general perception among the rank and file regarding seeking counseling.

"He was an introverted guy, quiet," Leatherman said.

Terrence Russell of the Pentagon's Joint Personnel Recovery Agency, who debriefed Bergdahl after he returned from captivity, also testified today, saying he thinks Bergdahl "did the best job he could do and I respect him for it."

Russell described conditions of “absolute torture and horror” during Bergdahl’s captivity. Russell said Bergdahl told him he escaped for 10 minutes two days after his capture. The Taliban group recaptured him, blindfolded him and beat him with a rubber hose, he told Russell.

After the escape, Bergdahl told Russell that his arms and legs were tied to a bed frame and they beat him with a copper cable for three months.

Russell said Bergdahl spent three and a half years inside a cage.

Curtis Aberle, a nurse practitioner at Fort Sam Houston who has been treating Bergdahl, said today Bergdahl has been diagnosed with post-traumatic stress disorder.

Aberle said Bergdahl told him that during his captivity he was held in a crouched position that compressed the nerves from the knees and below. He suffers from muscular nerve damage, Aberle said. He also has degenerative discs in his back and his left shoulder is injured, Aberle said.

Bergdahl should not remain in the military and will require lifetime care, Aberle said.

The prosecution said Bergdahl had "deliberate and knowing disregard" for his fellow soldiers by leaving "under the cover of darkness," and brought up the brutal search the soldiers were forced to endure in the heat and cold.

“There are consequences to those actions ... and those consequences should be a court martial," prosecutor Margaret Kurz said.

In closing arguments, Bergdahl's attorney reiterated that Bergdahl's motivations were innocent and that he wished to complain to a general about perceived problems in a unit.

The Associated Press contributed to this report.

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