'One of the best guys I know': Players, coaches mourn loss of 'hero' coach in Fla. school shooting Authorities said Aaron Feis died while "protecting others" at the high school.

 -- A Marjory Stoneman Douglas High School football player who joined teammates and coaches in an interview that aired Friday on “Good Morning America” remembered slain coach and campus monitor Aaron Feis as “one of the best guys I know.”

Broward County Sheriff Scott Israel had said Feis, who was among the 17 people gunned down in a mass shooting at the school Wednesday, died while saving lives, though was unable to provide details.

But the particulars don’t matter to grieving players like Robbie Rodriguez, a junior on the Marjory Stoneman Douglas High School football team.

Coach Feis, 37, was “one of the best guys I know; just open-hearted, open to anyone, always there for people. If you needed him [he was] on his golf cart, rolling right to you,” said Rodriguez, referring to the coach’s method of transportation around school campus.

Others players expressed similar sentiments.

“Say someone messed up, he wouldn't come over screaming at you,” sophomore Gage Gaynor told “GMA." “He'd come over, tell you what you did wrong, tell you how you could do it right.”

Teammate Patrick Scullen, a junior, called Feis a “great coach [and] great man.”

“He always put a smile on my face every single day,” Patrick added.

Team head coach Willis May shared his shock on hearing the news, adding it will be tough to return to coaching without Feis not by his side.

“I didn't want to believe it, I didn't want it to be true,” May told “GMA.” “I love him … things are going to be real hard to go back to school and not see my buddy.”

May called Feis a “hero” even before the deadly shooting.

“He didn't need to get shot to be a hero … he was a hero every day because people looked up to him, respected him … it's not a high-paying job,” May said, “but if you can change somebody's life you know and make him into a better person, that's what it's all about.”

The Broward County sheriff confirmed the death of Feis at a press conference Thursday morning.

"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," he 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. Although the two didn't keep in touch much after high school, Mackman said he remembers Feis as a people person and football fanatic.

"I never thought something like this could happen," Mackman, now 37, told ABC News in a telephone interview Thursday. "The whole community is just stunned."

Mackman said he heard from other former classmates who were close with Feis that he was apparently shot while shielding students from the spray of bullets.

"He was always a really good guy," Mackman said. "But the fact that he died saving lives, the guy's a hero. There's no two ways about it. He was always a giving guy, he was always there for people, he had a big heart. That showed all the way to the end."

Gabrielle Pupo, a student who survived the shooting, said she saw the gunman go after Feis.

"When I took my headphones off, the alarm was going off, and I heard the shots. And then I saw the shooter run after Mr. Feis, and I saw Mr. Feis get shot," Pupo tearfully old ABC News in an interview Wednesday night.

The alleged shooter, 19-year-old Nikolas Cruz, was arrested for premeditated murder and held without bond Thursday afternoon, authorities said. Marjory Stoneman Douglas High School remained the rest of the week, according to Broward County Public Schools Superintendent Robert Runcie.

Cruz had been expelled from the high school for unspecified disciplinary reasons, authorities said. A former classmate and a former teacher told ABC News that Cruz was barred from carrying a backpack on campus prior to his expulsion.

Wednesday's school shooting is among the deadliest in U.S. history. Cruz allegedly used an AR-15-style rifle that he legally purchased within the past year from a federally licensed dealer, law enforcement officials told ABC News.

ABC News' Brent Black, Aaron Katersky, Josh Margolin, Michael Rothman, Matthew Stone and Scott Withers contributed to this report.