WASHINGTON -- He prayed every day at the Muslim Community Center in Silver Spring, Md., a devout Muslim who -- despite asking to be discharged from the U.S. Army, according to his aunt -- was on the eve of his first deployment to war.

Yesterday, authorities said Maj. Nidal M. Hasan, a 39-year-old Arlington, Va.-born psychiatrist, shot and killed at least 12 people at Fort Hood, Texas.

In an interview, his aunt, Noel Hasan of Falls Church, Va., said he had endured name-calling and harassment about his Muslim faith for years after the Sept. 11, 2001, attacks and had sought for several years to be discharged from the military.

"I know what that is like; I have experienced it myself while working as a bank executive," she said. "Some people can take it, and some cannot. He had listened to all of that, and he wanted out of the military, and they would not let him leave, even after he offered to repay" for his medical training.

Army spokesman George Wright said he could not confirm the report of any request to be discharged.

As authorities scrambled to figure out what happened at Fort Hood, a hazy and contradictory picture emerged of a man who received all his medical training from the military and spent all of his career in the Army, yet turned so violently against his own. Maj. Hasan spent much of his professional career at Walter Reed Army Medical Center in Washington, D.C., caring for victims of trauma, yet he spoke openly of his deep opposition to the wars in Iraq and Afghanistan.

Co-workers said he steered clear of female colleagues and, despite devout religious practices, listed himself in Army records as having no religious preference.

Authorities said Maj. Hasan, who was shot while being taken into custody, was in stable condition at a hospital last night.

Maj. Hasan is a 1997 graduate of Virginia Tech who went on to get a doctorate in psychiatry from the Uniformed Services University of the Health Sciences in Bethesda, Md. From 2003 through last summer, he was an intern, resident and then fellow at Walter Reed, where he worked as a liaison between wounded soldiers and the hospital's psychiatry staff. He was also a fellow at the Center for the Study of Traumatic Stress at the Bethesda military medical school.

He had been affected by the physical and mental injuries he saw working as a psychiatrist at Walter Reed for nearly eight years, according to his aunt.

"Some people can take that, and some can't," Noel Hasan said. "He must have snapped. They ignored him. It was not hard to know when he was upset. He was not a fighter, even as a child and young man. But when he [gets] upset, his face turns red. You can read him in his face."

Maj. Hasan "did not make many friends" and "did not make friends fast," his aunt said. He had no girlfriend and was not married. "He would tell us the military was his life," she said.

At the Muslim Community Center, Maj. Hasan stood out because he would sometimes show up in Army fatigues, said Faizul Khan, the former imam there. "He came to mosque one or two times to see if there were any suitable girls to marry," the imam said. "I don't think he ever had a match, because he had too many conditions. He wanted a girl who was very religious, prays five times a day, which is all very good."

In search of a partner in marriage, Maj. Hasan wrote in an application filed with a local Muslim matching service that "I am quiet and reserved until more familiar with person. Funny, caring and personable."

"He was a very quiet and private person. I can't say that people knew him very well, other than attending prayers," said Arshad Qureshi, chairman of the board of trustees at the Muslim Community Center of Silver Spring. "You didn't see him attend anything -- school for children or celebrations. He did not go out of the way to engage people. We have thousands of people who come through to pray; he was just one of them."

A Walter Reed co-worker said Maj. Hasan would not allow his photo to be taken with female co-workers, which became an issue during Christmas season, when employees often took group photos. Co-workers would find a solo photo of Maj. Hasan and post it on the bulletin board without his permission.

Rep. Michael McCaul, R-Texas, told reporters after a briefing on the shootings that Maj. Hasan was born in Virginia to parents who immigrated from Jordan.

The major was polite and respectful, said 1st Lt. Elizabeth Whiteside, who was treated by Maj. Hasan at Walter Reed while recovering from a gunshot wound suffered while in Iraq.

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.