Fort Hood, Texas (CNN) -- Testimony was scheduled to continue Wednesday in the military hearing of the accused Fort Hood shooter, a day after witnesses gave vivid details of the fleeting moments when people rushed to save the wounded at the Texas military base.
Even before the Fort Hood shooting ended, nurses and medics rushed to help the wounded, one witness said Tuesday.
"Nurses and medics get the [expletive] out here now -- we have soldiers bleeding," Sgt. First Class Maria Guerra recalled herself yelling. "You train for this, you train for this, let's go," she said as civilians and soldiers came out of hiding to save their fallen buddies.
Guerra was one of the many who have testified at the military hearing for Army Maj. Nidal Hasan. The hearing is a step toward a possible court martial and a death penalty for Hasan. Hasan is accused of killing 13 people and wounding dozens others during a shooting rampage at Fort Hood military base last November.
During testimony Tuesday Guerra said she could still hear shooting outside the building as she secured the doors with her own belt.
She saw the shooter, whom she later identified as Hasan, walking and firing his weapon. She said she recognized Hasan from an argument a week earlier over getting his small pox vaccination.
The building where scores of soldiers were getting immunizations and medical screening prior to shipping out for Afghanistan and Iraq was suddenly dark, the smoke from gunshots obscuring overhead lights.
Guerra said she urged the medical workers to "triage" the wounded, dividing them into groups and separating those who were already dead or too severely wounded to receive treatment.
Moments later came word that the shooter had himself been wounded. "I started yelling 'The shooter is down, they got the shooter,' triage, triage everyone, let's go."
Guerra used a marker to write the letter "D" on the foreheads of the dead and the time of death, urging the medical workers to save the living. "If they are dead, you've got to move on," she recalled yelling to her staff.
The prosecution presented nine more witnesses Tuesday, making a total of 48 since the Article 32 hearing began last week.
The Army psychiatrist, wearing his usual fleece watchcap, combat fatigues and combat boots, gave no outward sign of hearing the grisly testimony about the shootings.
Also Tuesday afternoon prosecutors played a third 911 tape, again with the distinct sounds of rapid gunfire.
At least one spectator in the front row, where relatives of victims sit, wept as the tape was played. And the woman who made the call, Shemaka Hairston, a civilian nurse, broke down on the witness stand as she gave her description of what happened.
"The shooter just came in and started shooting soldiers," she told the emergency operator. "We don't know who he is."
Retired Sgt. First Class Ingar Campbell said she told everyone to hit the floor when she heard the first shots. "It was complete chaos in our building ... gunfire and cries of agony," Campbell said.
Guerra said she saw the suspect reload three times before moving in her direction. "He dropped the magazine and up came another one and he reloaded so efficiently, very quickly," she said. She said Hasan was wearing a plastic identification card from the post hospital. "That [expletive] was wearing a badge, he was wearing a badge," she said.
In earlier testimony Tuesday, a witness described the sound of the guman's footsteps.
"Clack, clack, clack" could be heard as the shooter walked down a hallway in the seconds following the rampages, the witness said.