LA school evacuated after Ex-Miami Dolphins player Jonathan Martin threatened a shooting.

Youth is actually not wasted on the young - it gives them fresh insights to old problems.

Educators don't need to be trained to take out potential school shooters.

Trump says he's considering backing trained school employees to carry concealed weapons.

He has been hailed a hero for holding the door open so his classmates could flee gunfire.

Trump says he is open to improving checking system.

A string of copycat threats sweep the country in the wake of the Florida massacre.

The students at Florida's Douglas High are amazing communicators. That could save lives.

Vocal outbursts, disturbing drawings of figures with guns, constant disciplinary issues.

Nikolas Cruz's younger brother "is involuntarily committed to a psychiatric facility".

Details have emerged of how unstable Nikolas Cruz had become via social media accounts.

Usually in America the perpetrators don't survive. So what happened to those who did?

Math teacher at Stoneman Douglas High School refused to let anyone in, even the SWAT team.

Disturbing video emerged of Florida shooter doing target practice while wearing Trump hat.

At least 17 people are now feared dead and many people are injured in a Florida high school shooting on what is Valentine's Day in the US.

Scene from staging area near Marjory Stoneman Douglas High School. Source: @Grumpyhaus

In the Connecticut village of Sandy Hook, a New England community of picture-postcard beauty, preparations are in full swing for Christmas.

A suspected gang member opened fire on a group outside a Portland high school, sending three young people to the hospital in what police said appeared to be a gang-related shooting.

Just 12km from Columbine and ahead of the Sandy Hook massacre's first anniversary, a teenage gunman again opened fire at a suburban high school.

Recordings of 911 calls during the Sandy Hook shooting show dispatchers urged panicked callers to take cover and mobilised help as gunfire sounded in the background.

Adam Lanza may have hinted at his deadly plans online in the days before last year's Sandy Hook Elementary School massacre.

The student who wounded two classmates and killed a teacher and then himself on a Nevada middle school campus was 12 years old.

A teacher was killed and two students critically injured in a school shooting this morning in Nevada, which also left the schoolboy gunman dead.

Senate Republicans have scuttled the most far-reaching gun control legislation in two decades, rejecting tighter background checks for buyers and a ban on assault weapons.

Former prime minister John Howard has shared his experience in overhauling Australia's gun laws in one of the United States' most influential newspapers.