BUFFALO, N.Y. (AP) — On Saturday afternoon, a white gunman in body armor killed 10 Black shoppers and workers at a supermarket in Buffalo, New York. Another Black person and two white people were wounded. Federal officials are investigating the shooting as a hate crime; a state-level murder case is already underway.

A look at what we know so far:

WHAT HAPPENED IN BUFFALO?

The gunman opened fire at around 2:30 p.m. Saturday outside Tops Friendly Market, a supermarket in a predominantly Black neighborhood in the western New York city.

The gunman began shooting in the parking lot. Inside, he exchanged gunfire with a security guard, who was killed, as he stalked through the aisles shooting shoppers.

Wearing a helmet camera, the gunman livestreamed the shooting on Twitch. The gaming platform said it took down the video in less than two minutes.

At one point, the video shows, he aimed at a white person hiding behind a checkout counter, but said “Sorry!” and didn’t shoot.

When police confronted the gunman as he exited the store, he put his rifle to his neck. He then dropped the gun and surrendered.

WHO ARE THE VICTIMS?

Police said the 13 victims, including the wounded, ranged in age from 20 to 86. Most were over age 50.

The security guard, retired Buffalo police officer Aaron Salter, 55, drew words of praise from President Joe Biden for his selfless efforts to stop the bloodshed.

The dead included Heyward Patterson, 67, a church deacon who was at Tops to give rides to shoppers who needed them, and Ruth Whitfield, 86, who had just come from her daily visit to her husband in his nursing home. Andre Mackneil, 53, was picking up a cake for a child’s birthday. Katherine Massey, 72, was “a beautiful soul” who was killed while shopping, sister Barbara Massey said.

Celestine Chaney’s family learned of the 65-year-old’s death in the massacre from seeing the gunman’s video as it circulated online. The mother of Roberta Drury, 32, also saw the horrifying images.

The others killed in the shooting were Margus D. Morrison, 52, Geraldine Talley, 62, and Pearl Young, 77. The injured included three people who worked at Tops: Zaire Goodman, 20, Jennifer Warrington, 50, and Christopher Braden, 55.

WHO IS THE ACCUSED GUNMAN?

Police have identified the gunman as Payton Gendron, 18. He lived with his family in Conklin, New York, a small town about 200 miles (320 kilometers) southeast of Buffalo.

He graduated from high school in June 2021 — two weeks after state police took him to a hospital for a psychiatric evaluation after he said he aspired to murder-suicide, according to authorities. He was released about a day later. Officials said there was no specific threat or basis for criminal charges.

He told authorities it was a joke — but it really wasn’t, according to an online diary that recounts months of active, detailed planning for a livestreamed attack on Black people. The diary, kept on the chat platform Discord, was private until about a half-hour before the shooting, when a small group of users got invitations to view it, and some accepted, the company said. Discord said it removed the diary upon learning of it.

Investigators have said they are looking into all Gendron’s social media postings.

A separate, online screed that he apparently authored says the attack was meant to terrorize nonwhite, non-Christian people into fleeing the U.S. The diatribe resounds with white supremacist, anti-immigrant and antisemitic beliefs that reflect an increasingly prominent conspiracy theory about a plot to reduce white people’s global influence by “replacing” them. In a visit to Buffalo on Tuesday, Biden called on the nation to “reject the lie.”

Buffalo Police Commissioner Joseph Gramaglia has called the massacre “an absolute racist hate crime” by a man with hate in his “heart, soul and mind.”

Gendron has pleaded not guilty, and his lawyers have declined to comment. He is jailed ahead of a court hearing Thursday.

WHAT DO WE KNOW ABOUT THE RIFLE USED IN THE SHOOTING?

Officials said the AR-15-style rifle was purchased legally, but New York doesn’t allow sales of the ammunition magazines that were used.

Gendron bought the weapon within the past few months at a store near his home. Vintage Firearms owner Robert Donald said he has records of the sale but didn’t recall Gendron or the transaction. He said Gendron passed an instant background check on the day he bought the weapon.

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