EDGEWOOD (KDKA) — A former student and principal from Columbine High School spoke about school violence and safety measures on the heels of a government report that looked at targeted school violence.

A new study released Thursday by the Secret Service found that most school shooters displayed warning signs and the tragedies could have been prevented.

READ MORE: Penguins Forward Teddy Blueger Undergoes Surgery For Fractured Jaw

School leaders and police gathered at the Western Pennsylvania School For The Deaf to listen as former Columbine principal Frank DeAngelis and student Sister Mary Gianna spoke about school violence and safety.

“I encountered a gunman, I had to tell the families that the kids had lost their lives in my school,” DeAngelis said.

That incredible tragedy at Columbine High School in 1999 changed the purpose of the former principal’s life forever.

“They are all of our kids, and I want to make sure no community has to go through what we did,” DeAngelis said.

(Photo Credit: KDKA)

It also changed the life of a former student, Sister Mary Gianna of The Ark and The Dove.

Something told her to leave school before the shooting happened.

READ MORE: Pa. Liquor Control Board Hosting Rare Whiskey Auction

“As we were driving away from school, I looked in my rearview mirror and I noticed hundreds and hundreds of my schoolmates running out of the school,” Sister Gianna said.

Sister Mary Gianna said she began partying and drinking after the tragedy.

“I just lost all hope,” she said. “And it was in those moments that one of my friends that I had gone to parties with invited me to church with her.”

Many schools have implemented safety changes since the Columbine tragedy.

Metal detectors, school resource officers, and active shooter training have been added, as have programs like “Safe To Say.”

“We’re talking about mental health, we’re talking about bullying, we’re talking about suburban, urban,” Fred Livingston with the Edgewood police said.

The report released by the Secret Service was based on 41 incidents that took place in American schools from 2008 to 2017.

It found attackers usually had multiple motives — commonly a grievance with classmates — most attackers used firearms acquired from the home and all attackers exhibited concerning behaviors that communicated their intention to attack.

MORE NEWS: Carrick Residents Frustrated Some Streets Never Get Plowed

Approximately 40 school districts were invited to participate in Thursday’s event.