Columbine High School massacre, 20 years on: How the terror unfolded that fateful day in April

Columbine High School massacre, 20 years on: How the terror unfolded that fateful day in April
(Source : Getty Images)

It has been 20 years since April 20, 1999, when 12th-grade senior students Eric Harris and Dylan Klebold shot dead 12 students and one teacher at the Columbine High School in Colorado, before killing themselves.

Ten of these students were killed in the library where Harris and Klebold finally took their own lives. Just before the turn of the millennium, the incident at Columbine was considered the deadliest mass shooting at a high school in US history.

The horrific crime has since inspired several copycats, and the word "Columbine" has now become the word that is associated with school shootings. For the 20th anniversary of this crime, we take a look at what exactly went down in what should have been a normal day at Columbine High School.

A memorial for 13 victims stands around the graves of three of the Columbine High School shooting victims at Chapel Hill Memorial Gardens April 20, 2007, in Littleton, Colorado (Source: Kevin Moloney/Getty Images)


On the morning of the fateful day, at around 11:10 am, Harris and Klebold arrived separately at the school. Harris parked his car in the junior student parking lot while Klebold parked in the senior parking lot. The school cafeteria was their primary target for the bombs they had assembled. The library, which was the second venue for the shooting, was located right above the cafeteria on the second story of the building. Each of their cars also contained bombs that were timed to go off at 12 pm.

The pair of shooters armed themselves heavily and took their backpacks and duffel bags filled with pipe bombs and ammunition into the school. Harris had his shotgun in one of these bags. Harris and Klebold walked into the school cafeteria and placed two duffel bags which contained propane bombs. The bombs were set to go off at 11:17 am, which was lunch shift "A".

No witnesses recalled seeing the bags being added to the 400 odd backpacks that were already in the cafeteria. The security staff also did not observe the bags being placed there. A custodian had been replacing the school security videotape at around 11:14 a.m., which is believed to be the time that the bags were dropped off.


At 11:19 am, Klebold threw a pipe bomb towards the parking lot but it only partially detonated. The students sitting on the grassy lawn out front thought it was a prank by some seniors when suddenly, there was gunfire.

Many students were shot at outside the cafeteria, with some being gravely injured, before the shooters moved into the building. They soon moved towards the library where more students were shot at, out of which 10 were killed.  

Pipe casings used for pipe bombs, which were never exploded, are shown on display at the Jefferson County Fairgrounds February 26, 2004, in Golden, Colorado (Source: Mark Leffingwell/Getty Images)


The authorities responded to radio calls for help from the school at 11:22 am. The shooters finally walked out of the library at 11:36 am. putting an end to the hostage situation inside the library. Fearing the return of the crazed shooters, 29 uninjured and 10 injured survivors started evacuating the library through the north door. This led to the sidewalk adjacent to the west entrance of the school.


Harris and Klebold reentered the library after having failed to detonate the cafeteria bombs so that they could watch their car bombs go off. They had been set to explode at noon but they failed as well. At 12:02 pm, the students shot through the west windows at the authorities who had arrived at the school and who returned fire.

Nobody was injured in this exchange.

Chairs with bullet holes in the seat backs taken from Columbine High School are shown on display at the Jefferson County Fairgrounds February 26, 2004, in Golden, Colorado (Source: Mark Leffingwell/Getty Images)


By 12:08 pm, less than an hour after they started their shooting spree, the shooters took their own lives.

Harris reportedly sat down with his back to a bookshelf and fired his powerful shotgun through the roof of his mouth while Klebold went down on his knees and shot himself in the left temple with his TEC-9.

It was nothing short of a miracle that the cafeteria bombs failed to go off. If these bombs had exploded with the intended power, they could have killed or severely wounded all of the 488 students who were inside the cafeteria at the time. The explosion could have also possibly made the cafetaria's ceiling collapse, bringing down the library above it.


Propane tanks, kerosene, camping fuel, timers and clothing are shown on display at the Jefferson County Fairgrounds February 26, 2004, in Golden, Colorado (Source: Mark Leffingwell/Getty Images)


A total of 188 rounds of ammunition were reportedly fired by the shooters during the massacre. Harris is said to have fired almost twice as much as Klebold by firing his carbine rifle 96 times and his shotgun 25 times.

Klebold fired the TEC-9 handgun 55 times, and discharged 12 rounds from his double-barreled shotgun.

Law enforcement officers reportedly fired 141 rounds during the exchange of gunfire with the shooters.

According to the journals and videos, Harris and Klebold had hoped that after detonating their homemade bombs in the cafeteria during the busiest lunch hour with the hope of killing hundreds of students, they would shoot, stab, and even toss more bombs at the survivors who ran from the school.


The purpose of the car bombs was chillingly supposed to take out the police vehicles, ambulances, fire trucks, and reporters who came to the school responding to the situation.

Eric Harris (L) and Dylan Klebold examine a sawed-off shotgun at a makeshift shooting range March 6, 1999 in Douglas County, CO in this image from video released by the Jefferson County Sheriff's Department (Source: Jefferson County Sheriff's Department via Getty Images)


The FBI concluded later that the shooters had been victims of mental illness and that Harris was a clinical psychopath while Klebold suffered from depression.

Dr  Dwayne Fuselier, the supervisor in charge of the Columbine investigation, would later remark: "I believe Eric went to the school to kill and didn't care if he died, while Dylan wanted to die and didn't care if others died as well."


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