(CNN) - After Tuesday's shooting at an Oregon high school, many media outlets, including CNN, reported that there have been 74 school shootings in the past 18 months.
That's the time period since the December 2012 massacre at Sandy Hook Elementary School in Newtown, Connecticut, where 20 children and six adults were shot to death.
Without a doubt, that number is startling.
So on Wednesday, CNN took a closer look at the list, delving into the circumstances of each incident Everytown included.
Everytown says on its web site that it gleans its information from media reports and that its list includes school shootings involving a firearm discharged inside or on school grounds, including assaults, homicides, suicides and accidental shootings.
CNN determined that 15 of the incidents Everytown included were situations similar to the violence in Oregon - a minor or adult actively shooting inside or near a school. That works out to about one shooting every five weeks.
It is a sickening image that has become all too familiar to Americans around the country.
Students walking single file, arms raised, after a gunman opens fire inside their school.
This time, it happened at a high school just outside Portland, Oregon.
One student was shot and killed, and a teacher was injured. Multiple law enforcement officials tell CNN the gunman is dead from a self-inflicted wound.
Reynolds High School student Hannah League shares what she experienced during the shooting.
Pamela Brown has the latest details.
(CNN) - A gunman opened fired Thursday at Seattle Pacific University, killing one person and wounding three before a student tackled him, Seattle police said.
The gunman was reloading a shotgun when the student, working as a building monitor, knocked him down, Police Capt. Chris Fowler told reporters.
"Once on the ground, other students jumped on top of them and subdued the shooter," he said.
The suspect, whose identity was not immediately released, is in custody, police said.
The shooting began inside the foyer of Otto Miller Hall, which houses the university's science, math and engineering departments, when the gunman confronted three people and shot them, Fowler said.
In Philadelphia, a student allegedly fired a handgun inside his high school gym, injuring at least two students.
One suspect is now in custody, but police say they are searching for additional suspects as well.
CNN's Jason Carroll has the story OutFront.
(CNN) - He had a 20-gauge pump shotgun, which police say he personally sawed off.
He had three shells.
And he had a plan.
The 12-year-old had all these when he entered a Roswell, New Mexico, middle school gymnasium and opened fire, State Police Chief Pete Kassetas said Wednesday.
His first shot, which Kassetas characterized as "birdshot," hit the ceiling. The second went into the gym floor. The third sped toward the stands where, some 12 to 15 feet away, it hit two of a throng of students who had been waiting for classes to start.
"The victims were random," the state police chief said.
Having carried out three search warrants and conducted at least 60 "primary interviews," Kassetas laid out these and other details related to Tuesday morning's shooting at Berrendo Middle School. But he didn't disclose everything, including the preteen shooter's possible motive.
"We did find evidence that the suspect had planned this event," Kassetas said. "I can't discuss the particulars as to why."