Updated

CONKLIN, N.Y. – New details have emerged regarding the alleged threat that accused Buffalo mass shooter Payton Gendron made in June 2021, leading the teenager to undergo a required mental health evaluation at a local hospital. 

Payton Gendron, now 18, said he wanted "to commit a murder-suicide" in June 2021, prompting New York State Police to respond to the local high school and take the teen into custody, said Stephen Belongia, special agent-in-charge of the FBI’s Buffalo Field Office. 

Belongia provided the details during a joint FBI-DHS National Partner Call on Monday afternoon. FBI Director Christopher Wray, United States Secretary of Homeland Security Alejandro Mayorkas, Associate Attorney General for the Department of Justice Civil Rights Division Kristen Clarke and police and sheriff’s department officials from Buffalo also participated in Monday’s call. 

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"In June 2021, New York State Police in Binghamton, New York, received a call from the assistant principal of the local high school regarding the alleged killer," Belongia explained. "This principal reported the alleged killer responded to a question about post-graduation plans by stating he wanted to commit a murder suicide. New York State Police took him into custody under New York mental health laws and transported him to the hospital for evaluation."

On Sunday, a spokesperson for the New York State said troopers responded to Susquehanna High School in Conklin, N.Y., in June 2021 "to investigate a report that a 17-year-old student had made a threatening statement." The spokesperson did not identify the subject by name, but said there was no target associated with the threat. 

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Speaking to reporters that same day, Buffalo Police Commissioner Joseph Gramaglia said state police responded, investigated and "felt it was appropriate at that time to have that individual brought in for a mental health evaluation."

Gendron allegedly remained hospitalized for one-and-a-half days.

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"State police did their job to the fullest that they could at that time," Gramaglia went on. He later added: "He was evaluated, and then he was released. As far as when we say 'On the radar,' there was nothing picked up on the state police intelligence, nothing that was picked up on the FBI intelligence. Nobody called in. Nobody called any complaints."

On Sunday, Susquehanna Valley Central School District Superintendent Roland Doig wrote in a statement that school staff members were "unspeakably saddened by the news of the shooting in Buffalo."

"Our thoughts remain wit the victims and all of the families impacted by this tragedy," he wrote. "While law enforcement continues their investigation, we are providing mental health services and counselors for students and staff that need support."

Gendron, who is White, pulled up to the Tops grocery store around 2:30 p.m. Saturday and immediately began firing off shots – wounding four people in front of the market before making his way inside, Buffalo Police Commissioner Joseph Gramaglia said. Three of the four victims died. 

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Once inside, he exchanged fire with store security guard Aaron Salter, who was a retired police officer, officials have said. Salter fired several rounds at Gendron before the suspect fatally shot him, Gramaglia said.

Gendron then allegedly made his way around the store shooting several other victims. When confronted by police, Gendron placed the rifle to his neck before dropping the weapon and surrendering, the police chief said. 

Ten people were shot and killed. Three other people were injured.

Eleven of the victims were Black individuals, officials have said. 

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The deceased victims have been identified as: Roberta A. Drury, 32; Margus D. Morrison, 52; Andre Mackneil, 53; Aaron Salter, 55; Geraldine Talley, 62; Celestine Chaney, 65 ; Heyward Patterson, 67; Katherine Massey, 72; Pearl Young, 77; and Ruth Whitfield, 86.

Officials have said the suspect live-streamed a portion of the shooting on social media platform Twitch. A Twitch spokesperson said the stream was suspended within two minutes. Gendron also allegedly detailed his plans in an extensive, hate-filled manifesto. 

So far, investigators have found that Gendron was in possession of "three weapons. There were two in the car and one in his possession," Gramaglia said. 

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"One was a rifle, one was a shotgun … He had an AR-15" inside the store with him, the commissioner added.

Gendron was charged with first-degree murder. He was arraigned late Saturday and pleaded not guilty. He was ordered held without bail and is due back in court on Thursday.