On Friday, May 18, students at Santa Fe High School in Texas heard a fire alarm that one student said froze time. Once it became clear there was not a fire but actually an active shooter on campus, they were told to run. Since then, these brave students have taken to social media and spoken with reporters, describing what happened that day in their own words.

“God please protect my friends and everybody at the school,” a Santa Fe high school student tweeted after another student, Dimitrios Pagourtzis, surrendered to police after allegedly opening fire, killing 10 people and wounding an additional 10 on campus.

The attack began in the art room, and when students fled through the hallway, one student described the terror this way: “My friend got shot in the art hall. And as soon as the alarms went off, everybody just started running outside, and the next thing you know, everybody looks and you hear, ‘Boom, boom, boom.’”

The fire alarm the student describes was reportedly pulled by a teacher, Glenda Ann Perkins, whom students said died protecting them. On Twitter, a student named Lydia Swartz said Perkins pushed a student out of the way. Another student, Zac, credited her on Twitter with saving more lives: “[I don’t know] who pulled the fire alarm, but thank you for pulling it and helping me and my friends be safe.”

Not all students on campus understood that the fire alarm meant danger, though. One student describes hearing it and falling into the humdrum habits of a fire drill: “When the fire alarm was pulled, we…didn’t run, because I thought it was a fire alarm, so I left all my belongings, and I walked out like normal,” Presley Lummus told NBC News. That changed, she said, when the teachers started yelling, “Run, run!”

Students on Twitter also credited teachers such as Steve Rose as well as the school’s resrouce officers for providing a necessary sense of security during what was a scary, confusing, and unpredictable time. For Suzannah, whose sister Sarah Salazar was injured that day, she told a KHOU reporter that it took hours to find out what happened after hearing the gunshots.

Among the wounded is 16-year-old Rome Shubert, who had a bullet pass through the back of his head. On Twitter, he thanked God for surviving, and in an interview with ABC 13,he said, “I feel lucky to be here. I just wish this didn't happen. This shouldn't happen to anybody at that school. Nobody deserves that."

The bravery of survivors since the shooting has demonstrated how much heart was walking the halls of Sante Fe High School that day. One student, Ken, expressed disbelief on Twitter at how much had changed for them in so little time. She tweeted that the day of the shooting was supposed to be her last drama performance. The immediate response of a student named Paige went viral — she told reporters the shooting did not surprise her: “I’ve always felt it would eventually happen here, too.”

Sante Fe High School students are now grappling with the expectation that they will return to school, with the tragedy fresh not just in their memories but in the hallways they now have to learn to walk again. One student, Gracie, described dealing with symptoms of what sounds like post-traumatic stress syndrome, “Now anytime i hear sirens my heart stops for a second as I scan the area around me as fast as I can.” Another student simply tweeted, “I don’t know how they expect us to go back on Wednesday.”

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