FORT HOOD, Texas - A chaplain exhorted hundreds of mourners gathered at a candlelight vigil to not give up hope as Fort Hood and its surrounding community looked to each other for comfort after an Army psychiatrist allegedly went on a deadly shooting spree at the military post.

A grief counseling center was set up Friday at the Killeen Community Center to help residents struggling to make sense of one of the worst mass shootings ever on a military facility in the United States. At least 13 people died and more than two dozen were wounded in the attack a day earlier.

"Remember to keep breathing. ... Keep going," Douglas Carver, the Army’s chief chaplain, told the crowd of several hundred at the vigil, many dressed in fatigues and black berets.

The alleged gunman, Maj. Nidal Malik Hasan, was wounded and taken into custody after a gunfire exchange with two civilian police officers. At least 13 people died and more than two dozen were wounded.

Like other military installations nationwide, the bonds between Fort Hood and the town at its doorstep are tight. Town merchants depend on the soldiers who shop at their stores and eat at their restaurants. Locals show their appreciation and support for the troops, hoisting giant yellow ribbons and raising money for charities benefiting Fort Hood soldiers stationed in Iraq or Afghanistan.

"Most of our clientele are soldiers, so this affects everyone in the community," said James Carpenter, 34, a tattoo artist at Zombie Ink and a former soldier who had been stationed at Fort Hood before he left the Army in 2003. "Everyone is asking why and saying, ’I can’t believe he did that.’"

Witnesses said Hasan stood on a desk and began firing after walking into the Soldier Readiness Processing Center, where troops who are about to be deployed or who are returning undergo medical screening. Those who weren’t hit by direct fire were struck by rounds ricocheting off the desks and tile floor.

Officials say the gunman was stopped after two civilian police officers arrived on the scene and began a firefight with Hasan, who was hit four times including at least once in the torso.

Most of the shooting survivors remained hospitalized, many in intensive care. Former President George W. Bush and his wife, Laura, visited wounded soldiers Friday night at the post hospital. A Bush spokesman said the couple spoke with family members of the wounded and personally thanked hospital staff members and Fort Hood leaders.

Hasan was transferred Friday to Brooke Army Medical Center in San Antonio, about 150 miles southwest of Fort Hood. Army officials late Friday gave no indication of his condition except to say he was "not able to converse."

Some who knew Hasan said he may have been struggling with a pending deployment to Afghanistan and faced pressure in his work with distressed soldiers, although authorities still did not have a motive.

Hasan’s Palestinian uncle said his nephew loved America and wanted to serve his country.

Rafik Hamad, 64, told the Associated Press in the West Bank town of El-Bireh that Hasan had been harassed by other soldiers because of his Muslim faith but that he was not angry.

"He really wasn’t angry ... I felt that he feels sympathy for them because they are ignorant and that’s their level of understanding," Hamad said.

Fort Hood spokesman Col. John Rossi said that the assailant fired more than 100 rounds and that his weapons were not military arms, but "privately owned weapons ... purchased locally."

Shock over the shootings persisted into Friday night, when hundreds attended a candlelight vigil in the first formal community gathering since the killings. Earlier in the day, a moment of silence was held at U.S. military installations as a show of respect for the victims, and 13 flag-draped coffins departed from Fort Hood for Dover Air Force Base and the military’s mortuary based in Delaware.