Cruz was a student at Marjory Douglas and was known to teachers there as a kid who had problems. He had transferred between schools six times in three years, once to a school for students with emotional or learning disabilities.
At MSDHS, Cruz did well with his studies, averaging Bs in most of his classes, and an A in Jr. ROTC. He had one extracurricular activity at MSDHS – he was a member of the school’s air rifle team.
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The reasons Cruz went from troubled kid to mass killer are not well-known. Victims’ families, survivors and the public have yet to hear from Cruz as he is still awaiting trial on 17 charges of murder.
What is known is that he had family issues. He did not get along with the woman who adopted him soon after his birth.
One story claims he argued with his mother about Donald Trump – he liked him, she didn’t.
When she died, a family friend said, Cruz decided to get even with her on that score by putting a "Make America Great Again" hat in her casket and taking a photo of the dead woman with it.
What led to the shooting on Feb. 14, 2018?
Cruz was able to get into the school on Valentine’s Day and roam the halls for six minutes, shooting teachers and students. In an age of gated campuses, security checkpoints and resource officers staged throughout schools, how was Cruz able to do it?
A commission charged with answering that question came up with three reasons Cruz was able to kill 17 and injure 17 more – unlocked gates, locked doors and failures by the FBI before the incident and local law enforcement during it.
Those failures led to the most deadly school shooting in modern American history. Here, from the report of the Marjory Stoneman Douglas High School Public Safety Commission, is how it unfolded:
2:19:00 p.m. ET
An Uber driver drops Cruz off at MSDHS at 2:19 p.m. near a gate that had been opened to allow for dismissal traffic but had been left unattended by school security personnel. From that entry point, Cruz heads onto campus and toward Building 12.
Cruz is first spotted coming onto campus. Andrew Medina, a baseball coach assigned to be a school security monitor, sees Cruz as he is unlocking the gates to the school grounds. Medina is riding in a golf cart when he sees Cruz walk through one of the gates holding a rifle bag.
Medina recognizes Cruz, a former student, as “Crazy Boy,” according to the police report. Despite what he sees, he does not issue a Code Red to lock down Marjory Douglas, though he did notify another campus monitor that Cruz was spotted on the grounds.
Cruz enters the first floor of Building 12 on the school’s campus and goes into the stairwell. Investigators say David Taylor, the security monitor who was alerted by Medina, walks into the building from the opposite end and moves toward Cruz, then stops and turns around.
Taylor said later that he had intended to go back toward the opposite end of the hallway and go up the stairwell at that end of the building. He intended to confront Cruz on the second floor, he told police.
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Freshman Chris McKenna heads into Building 12 and turns to go into the stairwell where he sees Cruz standing, loading an AR-15 rifle. According to McKenna, Cruz says, "You'd better get out of here. Things are gonna start getting messy."
Fifteen seconds later, Cruz raises the rifle to begin shooting but lowers and looks at it as if to see if it is malfunctioning.
He raises the weapon again moments later and begins firing. He shoots and kills freshmen Martin Duque Anguiano, Luke Hoyer and Gina Montalto, three students who had entered the first-floor hallway moments before Cruz. He also shoots Ashley Baez, who is hit in the leg.
Taylor, who first saw Cruz in the first-floor hallway, hears the shots as he is going up the stairs. He runs on up to the second floor of Building 12 and goes into a janitor’s closet.
Back on the first floor, Cruz heads down the hallway, where he will fire through windows at students in their classrooms, some so startled by the attack they are shot as they sit in their desk seats. He will never enter a classroom during the shooting.
Cruz lowers his weapon for a second time as Baez runs from the alcove of the woman’s restroom into classroom 1210.
Cruz goes down on one knee in the hall outside of the alcove of classroom 1216 and removes two items from his bag – a knit ski-mask and a camouflage shirt. He places the items on the ground, but does not put them on nor does he take them with him as he moves down the hall.
McKenna runs from the building and sees Aaron Feis, a football coach and another campus monitor. He tells him what he saw -- Cruz loading a gun and telling him that things were about to get “messy.”
Cruz is on his feet again with the rifle raised to a firing position as he heads toward classrooms 1214 and 1215.
He fires into classroom 2014, killing two, Nicholas Dworet and Helena Ramsay, and injuring Isabel Chequer, Samantha Fuentes, Samantha Grady and Daniela Menescal.
Carmen Schentrup is killed in room 1215.
The first call for help is placed to the Coral Springs, Florida, 911 system. The operator later says gunshots could be heard in the background of the call. Precious moments are lost when operators relay the information to the Broward County Sheriff’s Department.
Feis drives McKenna on his golf cart to Building 13 and walks him to the doors, telling him to go inside.
He heads toward Building 12 but does not call for a Code Red.
Cruz leaves the area between classrooms 1214 and 1215.
Smoke from the shooting sets off a fire alarm in the school, which sends students and teachers flooding out of classrooms and into Cruz’s path.
Had a Code Red been called, students would likely have stayed in their classrooms, according to the report. Instead, when the fire alarm is triggered, the students and teachers are told to evacuate, leading some into Cruz’s line of fire.
At this time, Cruz is shooting into classroom 1216 for a second time. Between the two instances, eight people are hit.
Alyssa Alhadeff, Alaina Petty and Alex Schachter are killed. Five others, William Olson, Genesis Valentin, Justin Colton, Alexander Dworet and Kheshava Managapuram, are killed.
After the fire alarm is triggered, a group of students head out of their third-floor classrooms and down the hall toward the west end staircase, many screaming in panic as they hear shots and realize it is not a normal fire drill.
Feis returns to his golf cart and begins to drive to the area between Buildings 12 and 13 from the north.
As it becomes obvious that the school is under attack, the only armed law enforcement officer on campus, resource officer Scot Peterson, meets up with campus monitor Medina, and the two head toward Building 12 in Medina’s golf cart. There, they met up with Security Specialist Kelvin Greenleaf.
As they approach the building, they see Chris Hixon, the school’s athletic director, entering the doors at the west end of the building. He runs down the hallway toward the east end of the building as Cruz is leaving the area around rooms 1214 and 1215. Cruz shoots Hixon, who tries to get some cover by crawling to a nearby doorway between the elevator and the men’s restroom.
Peterson arrives at Building 12, draws his gun but remains outside of the building. Cruz finds Hixon in the doorway he had taken refuge in and shoots him a second time.
Hixon is alive as he is pulled toward the west doors by law enforcement at approximately 2:33:43. He is helped onto a golf cart and transported to the triage area. He later dies from his wounds.
Feis leaves McKenna at Building 13 and heads to Building 12 where he parks his golf cart. Feis approaches the door on the west side of the building that is a direct entry into the west stairwell.
Feis opens the door to the stairwell and immediately comes face-to-face with Cruz. Cruz shoots Feis, fatally wounding him.
Hearing what they believe are gunshots, many teachers on the second floor of the school building treat the incident as an active assailant situation and take proper precautions, getting students into classrooms, covering windows and locking doors.
As Cruz gets to the second floor, he finds an empty hallway.
Cruz fires into two of 10 rooms on the floor, but no one is injured. While Cruz was shooting, Peterson and Greenleaf fled south from the east side of Building 12 toward stairs near the northeast corner of Building 7. Peterson stays at that spot for the next 48 minutes.
On the third floor, where there is confusion after the fire alarm had gone off, teacher Ernest Rospierski is looking at the west stairwell and hearing the shots from below.
As Cruz fires again into classroom 1231, Rospierski runs to the west end of the third floor where students are beginning to run toward the stairwell.
Four seconds later, Cruz reaches the door to classroom 1234 and fires into the room. Students begin to run to the east stairwell to go up to the third floor. At the same time, students on the third floor are trying to get into classrooms to hide.
As Cruz is firing into classroom 1234, other students run west on the third floor toward Rospierski. Rospierski directs them into classrooms. Some try to get into classrooms but find doors locked.
Cruz moves to the stairwell as Rospierski and some students are still trying to get out of the hallway.
Cruz enters the east end of the third-floor hall. Two seconds later, at 2:24:32, Cruz fires west down the third-floor hall. He hits 10 people, of which six – Scott Beigel (teacher), Jaime Guttenberg, Cara Loughran, Joaquin Oliver, Meadow Pollack and Peter Wang – will die either immediately or within minutes of being shot.
Beigel is shot while holding the door for students to get into a classroom.
The other four -- Anthony Borges, Marian Kabachenko, Kyle Laman and Stacey Lippel (teacher) -- suffer injuries that are not life-threatening. Lippel, like Beigel, was holding a door to allow students to try to escape the attack.
Cruz gets an ammunition magazine from his vest as he turns and begins to walk east in the third-floor hall.
Rospierski and nine students duck into the alcove of his classroom as he fumbles for keys to unlock the door and get into the room. Two students shot as Cruz fired down the hallway, Oliver and Pollack, go into the alcove of the women’s restroom across the hall from Rospierski’s room. Laman runs into the alcove of the men’s restroom.
Oliver and Pollack then run from the alcove of the locked women’s restroom where Pollack rejoins Rospierski’s group across the hall and Oliver goes to the alcove of the locked men’s restroom.
Rospierski tries to get into the classroom next to his, but finds that door locked, as well.
Cruz turns and heads back toward the west at the same time Rospierski directs 10 students to run with him toward the west stairwell. Pollack, who had been shot by Cruz on the first floor before fleeing to the third floor in an attempt to get away, collapses as the group runs.
The first call for a Code Red comes at nearly 2:25, some three minutes after the first shots were fired. Campus Monitor Elliott Bonner called the code after he sees Feis on the ground outside the building and hears gunshots.
Cruz sees Rospierski fleeing with his group of students, raises his rifle and begins to shoot again. Jaime Guttenberg and Peter Wang nearly make the top of the stairwell before they are shot.
Wang dies in the hallway. The other eight students make it down the stairwell as Rospierski remains on the third-floor landing with Guttenberg who lays dying on the ground.
Cruz makes his way down the hall, sees Pollack and Loughran, one of the 10 initially shot on the third floor. Pollack is trying to get on top of Loughran to protect her from the gunman.
Cruz puts five more bullets in the two girls, killing them.
Cruz finds Oliver hiding in the men’s restroom alcove. He shoots and kills him.
Cruz fires several rounds to the west end of the building. Four seconds later, he reaches the door to the west stairwell and tries to open it. He can’t.
Rospierski is hiding behind it, keeping the door closed.
Cruz appears to try to set up a sniper nest in the teachers’ lounge left of the west stairwell. He tries to shoot out the windows on the south and west sides of the room.
2:27:03 to 2:27:10 p.m.
Cruz fires his last shots inside Marjory Stoneman Douglas High School.
Rospierski flees the third-floor landing of the west stairwell, runs down to the second floor and takes cover behind a locked door until he is found by law enforcement officials.
Cruz enters the west stairwell on the third floor, leaving his rifle, vest and 180 live rounds of ammunition on the ground, and runs down the stairs.
Later, when law enforcement reached the third floor, they would find that none of the dead on the building’s top floor are found in classrooms. Students were trapped in hallways as classroom and restroom doors were locked.
Cruz leaves the building at the west end and walks toward Building 6, turns left and meets up with a group of fleeing students.
A Coral Springs Police officer radios that Cruz was “…last seen in the three-story building, north parking lot.”
Assistant Principal Jeff Morford and school security officer Greenleaf start to review video footage of Building 12 to determine what happened. What they don’t realize is that the tape they are watching is on a 20-minute delay and the shooting is over.
Morford relays information about Cruz's whereabouts to Peterson, who has been out and away from the building.
Officers are told Cruz to continue searching for Cruz in the building — delaying aid to injured students.
Cruz joins a large group of students who were running west toward Westglades Middle School.
First responders enter Building 12 to a scene of carnage.
Students are running from school grounds as the search for Cruz continues in Building.
Cruz walks through the Walmart parking lot near the school.
Officers are told Cruz was last seen on the second floor of Building 12. They continue to slowly move through the building.
Cruz enters the Subway restaurant inside of Walmart and orders a drink.
Officers make it to the second floor of Building 12 in their search for Cruz, thinking he is holed-up in the school.
Cruz leaves Walmart.
Sheriff’s deputies are told Cruz has moved to the third floor of Building 12. During the next six minutes, law enforcement officers review the video of the attack to try to figure out if the video is showing what is going on in real-time.
Cruz enters a McDonald’s restaurant near the school and sits down with John Wilford. Wilford’s sister was one of those injured in the shooting.
Cruz leaves McDonald’s and walks south about the same time law enforcement authorities realize that Cruz fled Building 12 some 20 minutes earlier.
Fifteen of those shot on the first floor are still alive and are removed from Building 12. Two will die from their injuries.
Second-floor classrooms are checked by law enforcement, and four minutes later, the last surviving victim is removed by first responders.
All classrooms in Building 12 have been checked by law enforcement now.
Cruz is detained by an officer of the Coconut Creek Police Department approximately 2 miles southwest of the school. He matched the description of the shooter that had been sent out minutes before. He is taken into custody without incident.
FILE - In this Jan. 16, 2019, file photo, Parkland school shooting suspect Nikolas Cruz sits during a status hearing at the Broward Courthouse in Fort Lauderdale, Fla. The potential death penalty murder case against Cruz is moving slowly and could take years.