The investigation is intensifying at Fort Hood, Texas today.
And so are the emotions at the nation's largest military post.
The fallout from yesterday's massacre spilling over for many trying to understand what triggered the attack by one of their own.
"You don't expect to hear it, you don't. you always have the safe sense that nothing is going to happen when you are at home," said Army Sgt. Andrew Hagerman, a military policeman.
Late yesterday that home was ripped apart.
A fire-storm of bullets rained down on dozens of soldiers.
At least thirteen were killed, more than 30 rushed to area hospitals.
"Basically there was no region of body which there wasn't an injury in these patients. Gunshot wounds to the neck, head, chest, abdomen and extremities. Unfortunately in some of these individuals they were injured in several sites," says Dr. Roy Smythe of the Scott & White Hospital nearby.
And Army investigators say the most deadly attack ever on a U.S. military post was carried out by one of their own, Major Nidal Malik Hasan.
Security camera video obtained by CNN shows the alleged gunman at a convenience store just a few hours before the attack.
The clerk says nothing seemed out of the ordinary.
But others say there were troubling signs.
Just this week neighbors say Hasan gave away his furniture and many of his possessions.
A devout Muslim, there are reports he was frustrated after being ridiculed about his religion by other soldiers.
And that he had growing fears on the eve of his first deployment to the Afghanistan.
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