By I-Hsien Sherwood | i.sherwood@latinospost.com (staff@latinospost.com) | First Posted: Jan 08, 2013 12:46 PM EST

Police officers on the scene after the Aurora, Colo. theater shooting last summer described the carnage in graphic detail in the first court hearings in the case.

The chaos, bloodshed, and screams of victims and their loved ones contrasted with the calm and detached demeanor of the shooter, James Holmes, they said.

"He was just standing there not doing anything, not urgent about anything," testified Aurora police officer Jason Oviatt.

Inside the theater was a different matter.

In all, 12 people were killed in the massacre, and another 58 were wounded. There was so much blood, one officer said he slipped and almost fell in it.

Officer Justin Grizzle choked up on the witness stand, remembering how, as he transported victims to the hospital, there was so much blood, "I could hear it sloshing around in the back of my patrol car."

Holmes, a 25-year-old former doctoral student at the University of Colorado, is charged with 160 counts of murder and attempted murder. The preliminary hearings are considered a formality in this case, as there is a preponderance of evidence that Holmes was indeed the shooter in the early morning hours of July 20.

But the five days of testimony and evidence allow the defense to see what they must contend with if they are to pursue an insanity defense.

That is likely. Holmes seemed nonplussed as he sat in the courtroom while the officers gave their gruesome testimony.

He did not return their gazes or glance around the room at the victims and their families or the mass of journalists gathered to witness the proceedings.

Officers described Holmes as compliant, raising his hands when confronted by police just steps from the exit of the movie theater, lying on the ground when instructed to.

He didn't reach for his loaded guns, which were only a few feet away, and he didn't try to escape, even before police arrived.

He didn't fire on them, and, contrary to many mass shooters, didn't kill himself once he was done with his massacre.

But the determination of Holmes' mental state will be determined by state psychologists.

Most of the day's testimony centered on the harrowing scene officers were confronted with, and their frantic efforts to rescue the wounded and save as many lives as possible.

Grizzle told of a father who had been shot, who tried to jump out of the police car on the way to the hospital to go back to find his six-year-old daughter, who had also been shot. She later died from her wounds.

He also recalled screaming at a victim, telling him to stay alive.

"I thought he was going to die," Grizzle said. "I kept saying, 'Don't f---ing die on me.' He was making a god awful noise and when I heard that I would keep yelling."

"After I saw what I saw in the theater - horrific - I didn't want anyone else to die."

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