A group of doctors overseeing Nidal Malik Hasan's medical training discussed concerns about his overly zealous religious views and strange behavior months before the U.S. army major was accused of opening fire on soldiers and civilians at Fort Hood, Texas.

Doctors and staff overseeing Hasan's training viewed him at times as belligerent, defensive and argumentative in his frequent discussions of his Muslim faith, a military official told The Associated Press Wednesday.

As a psychiatrist in training, Hasan was characterized in meetings as a mediocre student and lazy worker, a matter of concern among the doctors and staff at Walter Reed Army Medical Center and the Uniformed Services University of the Health Sciences, the official said.

However, the group saw no evidence that Hasan, 39, was violent or a threat. It was more that he repeatedly referred to his strong religious views in discussions with classmates, his superiors and even in his research work, the official said.

The revelations about the concerns that Hasan's medical school teachers had about his behavior before sending him to Fort Hood come amid a growing debate over what warning signs the military missed before last week's shooting rampage that left 13 dead and 29 wounded.

The Pentagon has found no evidence that Hasan formally sought release from the army as a conscientious objector or for any other reason, two senior military officials told The Associated Press.

Family members have said he wanted to get out of the military and had sought legal advice, suggesting that Hasan's anxiety as a Muslim over his pending deployment overseas might have been a factor in the deadly rampage.

Scene 'confusing and chaotic,' police officer tells Oprah

Meanwhile, two civilian police officers who shot at Hasan during the Nov. 5 rampage spoke about the ordeal on The Oprah Winfrey Show on Wednesday.

Sgt. Kimberly Munley, 34, who was the first police officer on the scene and was hailed as a hero for intervening so quickly, said the scene when she arrived was "confusing and chaotic" but that she did remember getting shot.

Another civilian police officer, Sgt. Mark Todd, 42, arrived some time after Munley and also shot at Hasan.

Hasan, who was shot four times and remains in hospital in San Antonio, Tex., has not been formally charged but officials plan to charge him in military court, not a civilian one. He could face the death penalty.

Munley, who sustained three gunshot wounds in the confrontation, is out of the hospital after undergoing two surgeries. Todd was not wounded.

The casualty toll could have been much higher if the two officers had not intervened, officials said. Munley was directing traffic on the base when she got the call. She was at the scene of the shooting in less than four minutes, said Gen. George Casey, army chief of staff.

Todd said the Fort Hood shooting was the first time in his career that he had used his weapon. Munley said it will be a slow process to get back to her normal life but she knows she can do it.