Correction: an earlier version of this story included reports from the scene about the weapons used by the suspected shooter in Santa Fe, TX. This has been updated to reflect accurate information regarding the weapons used.

KUSA - Friday, May 18, 2018 – The country must again absorb reports of an active shooter at a Texas high school. As the day continued, more information became clear:

  • As many as 10 victims were killed in the incident.
  • The suspected shooter, a 17-year-old student, a handgun and shotgun with him.
  • Explosive devices were found near the school.
  • There may have been a second suspect involved

And as the country questioned this shooting, and mourns the death of more children, it’s impossible to forget the recent events and how details of this shooting may compare to others in our nation’s past.

In February, 9NEWS began digging and developing a list of school shootings – to help add perspective to the problem.

We are continuing to analyze data regarding potential school shootings that fit the criteria we used. We will continue to update this story with more information.

For a closer look at our list and sources, click here.

By combining FBI data with news reports, we managed to come up with a list of American school shootings. The entire list may be somewhat skewed, if only because the FBI started to earnestly track the data shortly after the Columbine High School shootings in 1999.

For this list, we decided only to count an act of violence where a shooter or shooters shot people in a school, apparently at random, or in an attempt to kill or harm many.

Those criteria leave our list considerably smaller than the list compiled compiled by Everytown for Gun Safety, which also includes shootings that were intended to be a suicide, but not hurt others, happened after hours, when school was not in session; and some instances where an off-duty officer or school resource officer’s weapon was accidentally discharged.

Using the parameters established by 9NEWS, there have been 13 school shootings so far this year.

9NEWS also established a sub-list, that focuses only on those shootings that fit the federal definition of mass shooting – or those that result in the deaths of three or more people, not including the shooter. To that extent, the shooting at Santa Fe High School is the second mass school shooting in 2018.

The shorter list is more comprehensive, as those were more often covered by media throughout history.

Altogether, these lists show school shootings have increased in frequency since Columbine.

Take a look at our data. Examine the trends. Tell us what you think.

We should say one thing really struck us: there were plenty of warning signs offered up in the months and years leading up to these horrific events. Few involved someone seemingly untroubled.

It tells us, each one of us can play a role in preventing future mass shootings.

In Colorado, this is a good place to start: Safe2Tell

Having trouble seeing the data? Click here

A special thanks to the following graphics gurus who put this animation together:

  • Tristan Peterson
  • Ty Stark
  • Bradley Coufal
  • Josh Blair
  • Emily Clawson
  • Hunter Mooney

For tips on this, or any other story, contact Chris Vanderveen, chris@9news.com or Katie Wilcox, katie.wilcox@9news.com