The Tulsa County district attorney said Thursday that no charges would be brought in the fight at an Oklahoma high school last month involving a nonbinary student, Nex Benedict, who died by suicide the next day.

District Attorney Stephen Kunzweiler announced his decision in a three-page letter that gave the fullest official account yet of the Feb. 7 fight at Owasso High School.

“From all of the evidence gathered, this fight was an instance of mutual combat,” Kunzweiler wrote.

The fight gained national attention after Nex’s death drew outrage from gay and transgender rights groups. They connected the death to the physical altercation and to what family members said was bullying at school.

This month, the state medical examiner released the results of its examination and found that Nex had died from “combined toxicity” of diphenhydramine, an antihistamine.