This timeline shows exactly how the Parkland shooting unfolded

The Miami Herald/Al Diaz via Getty ImagesSuzanne Devine Clark places stones at a memorial outside the school during the one year anniversary of the shooting death of 17 at Majory Stoneman Douglas High School Thursday, Feb. 14, 2019 in Parkland, Fla.
  • On February 14, 2018, a gunman opened fire at the Marjory Stoneman Douglas High School in Parkland, Florida.
  • The deadly school shooting left 17 students, faculty, and staff members killed, and another 17 injured.
  • This timeline, constructed from The Broward Sheriff’s Office official records and surveillance footage, outlines how the massacre unfolded.

One of the deadliest mass shootings in the United States took place one year ago at the Marjory Stoneman Douglas High School in Parkland, Florida.

Fewer than two hours after the gunfire first broke out, authorities arrested a single suspect: 19-year-old Nikolas Cruz, who had formerly been a student at the school.

The massacre left 17 students and staff members killed, and reignited a nationwide debate over gun control. Cruz remains behind bars, and could face the death penalty if prosecutors pursue a trial.

One year after the shooting, students, staff, and families have gathered at the school to remember the victims.

Here, moment by moment, is how the event unfolded.

Brennan Weiss contributed to an earlier version of this report.

2:19 p.m.: The suspect in the shooting, then-19-year-old Nikolas Cruz, arrived at Marjory Stoneman Douglas High School via an Uber.

Getty Images/Joe RaedleLaw enforcement officers stand outside Marjory Stoneman Douglas High School on the one year anniversary of the mass shooting on February 14, 2019 in Parkland, Florida.

Source: The Broward Sheriff’s Office

2:21 p.m.: He entered Building 12, walking into a stairwell with a black rifle bag. He opened fire within 15 seconds, firing into multiple classrooms.

YouTube/ABC NewsThe suspected Parkland shooter, Nikolas Cruz, can be seen on surveillance footage entering the high school building via a stairwell, carrying his AR-15 rifle.

Source: The Broward Sheriff’s Office

2:22 p.m.: The school’s fire alarm goes off, prompting students to begin evacuating. This is also when the first 911 call went out.

Joe Raedle/Getty ImagesPeople are brought out of the Marjory Stoneman Douglas High School during the shooting.

Source: Police records

2:23 p.m.: The school resource officer, Deputy Scot Peterson, issues a radio alert warning of shots fired. “Be advised we have possible — could be firecrackers. I think we have shots fired, possible shots fired, 1200 building,” he said.

Source: Police records

Peterson can be seen arriving at the southeast corner of Building 12, where he remained “for the duration of the incident,” according to video-surveillance records.

Screenshot via Miami HeraldDeputy Scot Peterson can be seen standing outside the building where a mass shooting took place at a Florida high school on February 14, 2018.

Read more: A damning new timeline of the Florida high-school shooting shows how badly the armed deputy screwed up

Peterson would later be severely criticised for failing to enter the building as students were being gunned down. He has maintained that he didn’t know where the gunfire was coming from.

Twitter/@TODAYshowScot Peterson spoke out about President Donald Trump’s comments calling him a coward after the mass shooting at a Parkland, Florida, high school on February 14.

Source: Business Insider

2:28 p.m.: Cruz exits the school and runs toward the tennis courts and heads south. He blends into a crowd of students as they flee the campus.

Source: The Broward Sheriff’s Office

2:32 p.m.: Four Coral Springs police officers and two Broward County sheriff’s deputies entered the building for the first time. The sheriff’s department would later face intense scrutiny over the length of time they waited before entering.

Source: Police records

2:50 p.m.: Cruz walks into a Walmart, buys a drink at the Subway restaurant inside, and leaves on foot.

Google MapsA map shows the Walmart where suspected gunman Nikolas Cruz headed after the shooting at the Marjory Stoneman Douglas High School.

Source: The Broward Sheriff’s Office

3:01 p.m.: Cruz then goes to a McDonald’s restaurant, sits down, then leaves on foot.

Source: The Broward Sheriff’s Office

3:41 p.m.: An officer with the Coconut Creek Police Department arrests Cruz in a nearby neighbourhood.

Google MapsPolice took the suspect into custody about two miles from the school.

Source: The Broward Sheriff’s Office

6:27 p.m.: Then-Broward County Sheriff Scott Israel announced that 17 people were killed in the shooting, and identifies Cruz as the suspect.^tfw

February 15, 2018: Cruz appears in court for the first time via video. He is charged with 17 counts of murder, and his public defender describes him as a “deeply troubled child who has endured a lot of emotional trauma in a short period of time.”

Source: Associated Press

March 14, 2018: A judge enters a “not guilty” plea on Cruz’s behalf. His attorneys have repeatedly offered to enter a guilty plea if prosecutors will vow not to pursue the death penalty. Prosecutors have rejected that deal, meaning a lengthy death-penalty trial is likely.

South Florida Sun-Sentinel/Amy Beth Bennett via Associated PressNikolas Cruz is lead into the courtroom before being arraigned at the Broward County Courthouse in Fort Lauderdale, Fla., on Wednesday, March 14, 2018.

Source: Business Insider

February 14, 2019: The one-year anniversary of the shooting occurs. Students, families, and staff members spend the day remembering the 14 students and 3 staff members who died.

South Florida Sun-Sentinel/Joe Cavaretta via Getty ImagesPeter Palmer of the Margate Fire and Rescue CERT chapter wipes away tears at the memorial garden outside of Marjory Stoneman Douglas High School Thursday, Feb. 14, 2019 in Parkland, Fla., on the one year anniversary of the shooting at the school.

Source: Associated Press

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