‘Someone help me.’ Video and audio evidence shake courtroom on opening day of Marjory Stoneman Douglas mass shooting trial

Prosecutor Mike Satz gave jurors an introduction to the horror of Feb. 14, 2018, telling them, “I’m going to speak to you about the unspeakable.”

Monday was the first day of the sentencing trial to determine if the confessed killer gets the death penalty or life in prison for the murder of 17 people at Marjory Stoneman Douglas High School in Parkland.

“He had been planning to be a school shooter long before he moved in with the Sneads [James and Kimberly], long before his mother passed away,” lead prosecutor Satz said.

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Satz said 139 shots were fired, 70 on the first floor, two in the west stairwell, six on the second floor, and 61 on the third floor.

The first witnesses appeared Monday afternoon, a former teacher and former students, describing harrowing details.

A cellphone video that was seen by the jury but only heard by the public in the courtroom gallery included many gunshots, an alarm going off, and many people screaming. Several people left the courtroom when they heard it.

A second audio clip introduced as evidence left the loud sound of the heavy gunfire echoing in the courtroom.

“Shut it off!” one family member pleaded from the audience.

The first 911 call, from former teacher Brittany Sinitch was played, where gunshots can be heard in the background.

Sinitch described the moment she heard the gunshots in the 1200 building of the high school. It was during the fourth period — nearing the end of the school day. Her students had been reading Romeo and Juliet and were writing Valentine’s Day cards when she heard “the loudest noise you could possibly imagine,” as she described in her testimony.

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There were no shots that entered her classroom, but Sinitch described the sound of gunfire as nonstop. She called 911 at the time, and the courtroom heard the call played back as part of her testimony on Monday.

She cried as she listened to the playback of the call, a series of gunshots echoing in the background of hers and the dispatcher’s voice.

Danielle Gilbert, who was then a Stoneman Douglas junior, was in a first-floor classroom where four students were shot, one fatally, Carmen Schentrup, after the killer shot through the window of the door. A teacher had the students attempt to hide behind her desk, she said.

“We were sitting ducks. There was no way to protect ourselves,” Gilbert said.

She turned on her cellphone video and started recording, which was shown to jurors. Gilbert grew visibly upset on the stand as the recording was played.

The audio included pleas from a boy, obviously in pain, moaning and pleading “Someone help me” several times as students talked about the bullets and whispered about police coming to get them.

But earlier in opening statements, Satz described the shootings in cold, clinical detail, pointing out not only who was shot but how many times, whether they survived, and the ages of those who died.

Satz recited the weapon’s serial number from memory. He recited details of each death, each injury, without consulting notes.

“All 17 were heinous, atrocious and cruel,” Satz said. “All 17 were cold. Calculated. Manipulative. And deadly.”

Satz described the killer walking over bodies to leave the school, taking off his vest and rifle, laying it down in the stairwell, and running out.

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Wearing a maroon JROTC Stoneman Douglas shirt, black pants and a blue baseball cap, gunman Nikolas Cruz ran out and blended in with students and teachers who were evacuating because a fire alarm had gone off, Satz said. The killer went to Walmart where he bought an Icee from the Subway before heading to a nearby McDonald’s.

At McDonalds, Cruz ran into student John Wilford, who didn’t know that Cruz had shot his sister, Maddy. Cruz asked Wilford for a ride, which he declined, saying he was waiting for him mom to pick him up, Satz said.

Cruz then started heading to a nearby subdivision where Coconut Creek Police Officer Mike Leonard saw him and arrested him, Satz said.

Emotions were visibly high in the courtroom. Some jurors struggled to keep their emotions in check, but most listened intently without flinching as Satz detailed every injury, every death on Valentine’s Day. Family members of victims also became emotional.

Fred Guttenberg, whose daughter Jaime was killed, wiped his eyes, then shook his head and mouthed to someone he was OK. Max Schacter, whose son Alex was killed, looked down, hand over face, shaking his head. Several women repeatedly dabbed at tears.

The trial began on Monday with questions about whether a juror had discussed the case prior to the trial.

Judge Elizabeth Scherer said she had an affidavit from someone saying that one juror had spoken with someone about the case, including the juror’s feelings about the death penalty. But the juror flatly denied it, saying it wasn’t true.

Scherer said she was inclined to believe the juror.

“I can’t take the word of someone I’ve never met with a juror I’ve spent hours with,” Scherer said. “The juror has never been anything but forthcoming.”

[ RELATED: What potential jurors can expect at the start of the Stoneman Douglas shooting trial ]

More than a dozen camera crews were set up outside the Broward County Courthouse in downtown Fort Lauderdale on Monday morning. The congestion closed down Southeast Sixth street and prompted curiosity from the public.

Passers-by — some aware of the Nikolas Cruz trial, some not — took in their surroundings. Their chatter floated through the building’s outdoor breezeway all the way up to the 17th floor.

“You see all that news right there?” “What floor is the trial on?” and “I just want to get over this whole nonsense.”

During the first break of the day, two observers left the courtroom on the 17th floor for bagels from the courthouse café on the ground level.

“Being in the same room as that guy [Cruz] is crazy,” one said to the other.

“Yeah, it must be so surreal for him,” the second replied.

This is a developing story, so check back for updates. Testimony is expected to begin at 1:30 p.m. Click here to have breaking news alerts sent directly to your inbox.