Accused grocery store gunman previously threatened to shoot up his school, officials say

A gunman accused of opening fire on a New York supermarket previously threatened to commit a mass shooting at his high school, and was sent for a mental health evaluation at the time, officials said.

The suspect armed with a rifle opened fire Saturday afternoon inside a supermarket in Buffalo, N.Y., killing 10 people and wounding three others in the latest mass shooting to strike America, police said.

Authorities said the shooting was being investigated as a racially motivated hate crime. The suspect, identified by police as 18-year-old Payton Gendron, was white. He allegedly shot 11 black people and two white people in his livestreamed rampage, authorities stated, according to The Associated Press.

Details of the shooting at the Tops Friendly Market were confirmed by law enforcement officials to AP.

Buffalo Police Commissioner Joseph Gramaglia said his victims included a retired police officer working security at the store.

He said the shooter traveled hours from outside the area to commit the crime, entering the store in body armor, streaming his shooting from a helmet camera. He went to the store at least one day before the shooting to scout out the area, officials said.

"It seems that he had come here to scope out the area, to do a little reconnaissance work on the area before he carried out his just evil, sickening act," Gramaglia told ABC on Sunday.

Police and witnesses told AP the gunman surrendered outside the store and was taken into custody. He was wearing military-style clothing and body armor, they said.

Video streaming platform Twitch said it cut Gendron's live stream of the massacre "less than two minutes after the violence started.”

Law enforcement told the AP that last June, Gendron threatened to commit a mass shooting at his high school, and Commissioner Gramaglia said the teen was taken in for a mental health evaluation at the time.

“He was standing there with the gun to his chin. We were like what the heck is going on? Why does this kid have a gun to his face?” witness  Braedyn Kephart said. “He dropped to his knees. He ripped off his helmet, dropped his gun, and was tackled by the police.”

New York Gov. Kathy Hochul asked residents to stay away from the scene, a predominantly African-American neighborhood a few miles from downtown Buffalo.

“I am closely monitoring the shooting at a grocery store in Buffalo. We have offered assistance to local officials. If you are in Buffalo, please avoid the area and follow guidance from law enforcement and local officials,” she tweeted.