Oxford High School Senior Austin Witt played football with 16-year-old Tate Myre-one of theon Tuesday when a student opened fire. 14-year-old Hana St. Juliana, 17-year old Madisyn Baldwin, and 17-year-old Justin Shilling were also killed.
Witt remembered Myre as always being happy.
"Honestly, he was the heart and soul of our team and probably our community. He's a true hero, and my thoughts and prayers go out to his family," Witt tearfully told CBS News' Nancy Chen.
The alleged shooter, who was identified as Ethan Crumbley, made his first court appearance on Wednesday and entered a plea of not guilty.
Investigators said there's a "mountain of digital evidence" that suggests Crumbley planned the attack in advance.
This includes a video law enforcement officials say Crumbley made the night before the shooting that mentioned killing students. A journal was also recovered from his backpack that detailed his desire to "shoot up the school," officials said.
Law enforcement officials said a social media post was also found that showed the gun used in the attack. It was purchased just four days before the shooting, investigators said.
The alleged shooter, who is being charged as an adult, faces 24 charges including one count of terrorism causing death and four counts of first-degree murder. Karen McDonald, the Oakland County prosecutor, said charging the teen as an adult "is necessary to achieve justice and protect the public."
"What about all the children who ran screaming, hiding under desks? What about all the children at home right now who can't eat, can't sleep, and can't imagine a world where they could ever step foot back in that school? Those are victims too," McDonald said,
Investigators said the suspect walked into a school bathroom around 12:50 local time Tuesday with a backpack and walked out with a gun in hand. He then walked down the hallway "aiming the firearm at students and firing," officials added.
Senior Mitchell Williams fled his classroom as soon as he heard the gunshots.
"It was horrific. It was really startling, hearing everyone come out and not knowing where the gunshots would be next," said Williams. "It's really sad and no one really knows what to do because of it and it's something that should have never happened."
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