The chilling story of the 16-year-old girl who shot 11 people because she "didn't like Mondays"

• Brenda Ann Spencer opened fire on Grover Cleveland Elementary School in 1979.

• She used a rifle her father gave her as a Christmas gift weeks before the attack.

• The shooting killed two school employees and injured eight children and a police officer.

• Her statement “I don’t like Mondays” later inspired a hit song by The Boomtown Rats.

On the morning of January 29, 1979, a quiet Monday in San Diego, California, turned into one of the most shocking school shootings in American history after a 16-year-old girl opened fire on an elementary school from the window of her home.

The teenager, Brenda Ann Spencer, lived directly opposite Grover Cleveland Elementary School in the San Carlos area of San Diego. Armed with a .22-calibre rifle, she fired at students and staff who were arriving at the school, killing two school employees and injuring several others.

The rifle used in the attack was not a weapon she had stolen. Weeks earlier, in December 1978, Spencer had received the .22-calibre rifle and ammunition as a Christmas gift from her father. The gift later became one of the most discussed details of the case because of what happened just a month later.

On the morning of the attack, Spencer positioned herself at her bedroom window and began firing across the street at Grover Cleveland Elementary School as children gathered outside before classes began.

The shooting lasted about 20 minutes. She fired dozens of rounds, with 11 people hit by the gunfire — including eight children, a police officer and two school staff members.

The two people killed were Burton Wragg, the school principal, and Michael Suchar, the school custodian.

Wragg was shot while responding to the attack and trying to help protect students, while Suchar was killed as he moved to assist during the chaos. San Diego police officer Robert Robb was also wounded while responding to the scene.

As gunfire continued, teachers moved students to safety while police surrounded Spencer’s home. Officers eventually began negotiations with her as she remained inside the house.

During the standoff, which lasted more than six hours, Spencer spoke by telephone with a reporter from the San Diego Tribune.

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When she was asked why she carried out the shooting, her response became one of the most infamous lines associated with a crime:

“I don’t like Mondays. This livens up the day.”

She also reportedly told the reporter that she had started shooting because it was a way to “cheer up” the day. The casual explanation shocked the public and became permanently linked to the case.

After several hours of negotiation, Spencer surrendered to police.

In the weeks before the shooting, reports said Spencer had displayed troubling behaviour, including incidents involving a BB gun and damage to windows at the same school she later attacked.

Some reports also said she had spoken about wanting to do something that would attract attention. However, the reasons behind her actions have remained a subject of discussion for decades.

Spencer was tried as an adult. In 1980, she pleaded guilty to two counts of murder and was sentenced to 25 years to life in prison.

Over the years, she has appeared before parole boards several times, but she has remained incarcerated.

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The strange phrase that Spencer gave as her explanation later inspired Irish rock band The Boomtown Rats’ 1979 hit song “I Don’t Like Mondays.”

The song, written by frontman Bob Geldof after he read reports about the shooting, became one of the band’s biggest hits and ensured that Spencer’s words became part of popular culture.

More than four decades later, the case remains remembered not only because of the violence of the attack, but also because of the shocking contrast between the seriousness of the crime and the teenager’s chilling explanation for it.