The first witnesses were called to the stand Monday as the sentencing trial of the Parkland school shooter began with emotional testimony and shocking audio from the day of the shooting.
Nikolas Cruz, 23, pleaded guilty in October to murder and attempted murder and is only contesting his sentence.
Prosecutor Michael Satz began with testimony from Brittany Sinitch, a former student at Marjory Stoneman Douglas High School who became a teacher at the school the year before the shooting.
Sinitch was in tears as she entered the courtroom and as she described the events of the Feb. 14, 2018 shooting that killed 17 and left 17 others wounded.
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“It was like you could feel [the gunfire] within your body, like, all throughout your chest,” she said.
The courtroom heard Sinitch's 911 call from her classroom, her voice drowned out by the sound of close gunfire.
“They couldn’t hear me over the sound of the gunshots,” Sinitch said. “It was so incredibly loud.”
Next to testify was was Danielle Gilbert, a junior who was in psychology class when the shooting began. The teacher told students to get behind her desk.
"We were sitting like sitting ducks. We had no way to protect ourselves,” said Gilbert, who is now a student at the University of Central Florida. Four people were shot in that room, she said, including one who died.
Videos recorded on Gilbert's cellphone were played in which a fire alarm, then gunshots, then whispering can be heard.
Wounded victims could also be heard before police officers are heard yelling as the school is evacuated, followed by crying.
“Is anybody injured?” police shouted.
“Yes,” the students yelled.
“Right here, right here,” students answered.
“Can you walk?” the officer asked. “Where were you shot?”
Other officers can be heard calling out, “I need help, arrrgh, I need help.”
At least two parents of victims left the courtroom while the audio was being played.
The third to testify was Dylan Kraemer, a former MSD student who is now in college.
Prosecutors played cellphone video from Kraemer that showed classmates crouching behind chairs as Cruz fired through the classroom door window, the bangs reverberating over screams. One woman in the back of the courtroom yelled for prosecutors to turn it off before bailiffs asked her to be quiet.
The defense team motioned for a mistrial citing the comment and arguing that might have negatively influenced the jury, but Broward Circuit Judge Elizabeth Scherer denied the motion.
Also called to testify Monday were former vice principal Maximo Rosario, and three FBI agents.