Officials said earlier in the day that the Butler High School student had been brought to a hospital in critical condition.
The disagreement occurred in a hallway and there were many "young people who witnessed this tragedy", Wilcox said.
In 2014, Butler High School was named as the fifth highest rated high school in North Carolina, by U.S. News and Report. CMS will provide updates throughout today, as warranted. Police said they believe the shooting was an "isolated incident", and authorities have secured the campus.
Dozens of parents gathered outside of the school of about 2,000 students.
A lockdown was lifted at the school Monday morning and parents were allowed to pick up their children.
Guardians and parents were advised of the incident via email and telephone calls, CMS said.
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Israeli military spokesman Lieutenant-Colonel Jonathan Conricus accused Syria and Iran of involvement in the attack. It blames Iran for orchestrating the rocket attacks against Israel, which were carried out by Islamic Jihad.
High school student Jorge Sanchez told WSOC-TV in Charlotte that the shooting happened as the result of an argument that escalated.
The school was placed in lockdown and then lifted at approximately 9:15 a.m.
The wounded student, a male, was taken to Carolinas Medical Center, police said, where he succumbed to his injuries. Classes were proceeding for students who remained on campus. In 2018, the school's graduation rate was over 91 percent. Wilcox said this was because students could only be released to family members or guardians. "He didn't feel safe".
"[CMS] is really going to have to look at security", she said.
Cuffie admitted to the crime and surrendered at the school, according to authorities.