(PARKLAND, Fla.) -- A football coach and a 14-year-old freshman were among the 17 people killed in a mass shooting at a South Florida high school Wednesday.
More than a dozen others were injured in the Valentine's Day rampage at Marjory Stoneman Douglas High School.
Here is what we know about the victims who have been identified by ABC News.
School football coach and Marjory Stoneman Douglas High School graduate Aaron Feis was one of the 17 killed, Broward County Sheriff Scott Israel said.
"When Aaron Feis died ... he did it protecting others, guarantee that because that's who Aaron Feis was," Israel told reporters. "He was one of the greatest people I knew. He was a phenomenal man."
The sheriff described Feis as a beloved football coach who was well-known in the local community.
"I coached with him. My two boys played for him," Israel said. "The kids in this community loved him, adored him."
Ryan Mackman of West Palm Beach said he grew up in Parkland and graduated with Feis from Marjory Stoneman Douglas High School in 1999.
The football team added on Twitter, "He selflessly shielded students from the shooter when he was shot. He died a hero and he will forever be in our hearts and memories."
Martin Duque, 14, was also killed. His older brother Miguel, who graduated from the same school last year, wrote on Instagram, "Words can not describe my pain. I love brother Martin you’ll be missed buddy. I know you’re in a better place."
Student Jamie Guttenberg was also among the dead.
Her father, Fred Guttenberg, wrote on Facebook today, "My heart is broken. Yesterday, Jennifer Bloom Guttenberg and I lost our baby girl to a violent shooting at her school. We lost our daughter and my son Jesse Guttenberg lost his sister. I am broken as I write this trying to figure out how my family get's through this."
He added, "Hugs to all and hold your children tight."
Teacher Scott Biegel died while saving others, according to student Kelsey Friend.
Friend told "Good Morning America" that Biegel unlocked a classroom door and started letting students inside.
"I had thought he was behind me ... but he wasn't," Friend said, crying.
"When he opened the door, he had to re-lock it so we can stay safe. And he didn't get the chance to," Friend said, noting that her teacher was lying on the floor.
"I'm so thankful he was there to help everybody," she added.
Gina Montalto also died in the shooting, her mother, Jennifer Montalto, said in a Facebook post.
"She was a smart, loving, caring, and strong girl who brightened any room she entered. She will be missed by our family for all eternity," the post said.
Athletic director and head wrestling coach Chris Hixon was among the victims, said Coral Springs High School athletic director Dan Jacob.
“Chris is probably the nicest guy I have ever met. He would give you the shirt off his back," Jacob said. "Chris has a son with Down syndrome. He put needs of everyone else before his own."
"It is so senseless," he added.
Alyssa Alhadeff, 15, was among the dead, said her older cousin, Ariella Del Quaglio, who wrote on Facebook, "My heart is broken."
"Alyssa Alhadeff was a loved and well respected member of our club and community," according to Ryan Block of the Parkland Soccer Club.
"Alyssa will be greatly missed," Block said. "Our thoughts and prayers go out to her family and all the other victims of this tragic event."
After the shooting authorities arrested the 19-year-old suspect who had been expelled from the school over disciplinary problems.
The school will be closed the rest of the week.
Copyright © 2018, ABC Radio. All rights reserved.