At least 10 people killed in live streamed shooting at New York supermarket

Police in Buffalo, New York, have described the killing of 10 people in a supermarket shooting as a racially motivated hate crime.

• An 18-year-old white man dressed in army fatigues was arrested at the scene
• Eleven of the 13 people struck by gunfire were black.
• Buffalo Mayor Byron Brown said the city had suffered a "tremendous heartbreak"

The offender live streamed the attack on the internet. 

An 18-year-old white man dressed in army fatigues was arrested at the scene of the killings after surrendering to police. He has been charged with first-degree murder but authorities say more charges could follow.

The FBI's special agent in charge, Stephen Belongia, said the bureau was investigating the shooting as both a hate crime and an act of racially motivated violent extremism.

The supermarket is in a predominantly black neighbourhood, about 5 kilometres north of downtown Buffalo.

New York Governor Kathy Hochul said it was a "military-style execution targeting people who simply want to buy groceries".

"It strikes us in our very heart to know that there's such evil that lurks out there," she said.

"Mark my words, we'll be aggressive in our pursuit of anyone who subscribes to the ideals professed by other white supremacists, and how there's a feeding frenzy on other social media platforms where hate festers hate. That has to stop."

Authorities said the offender, who was armed with an assault-style rifle and appeared to have acted alone, came to Buffalo from a New York county "hours away" to target the store.

Three people were also injured in the shooting, but are expected to survive. Eleven of the 13 people struck by gunfire were black and two were white, officials said. 

Buffalo police commissioner Joseph Gramaglia said the gunman shot and killed three people in the parking lot of the Tops Friendly Market before exchanging fire with a former police officer working as a security guard for the store.

The guard was one of the 10 people shot to death in the incident, the nine others all being customers. Three other employees of the store, part of a regional chain, were wounded.

Erie County Sherriff John Garcia said the shooting was "pure evil", while the city's Mayor, Byron Brown, said Buffalo had suffered "tremendous heartbreak", adding:

"This is the worst nightmare than any community can face and we are hurting and we are seething right now as a community. The depth of pain that families are feeling and that all of us are feeling can not even be explained."

Retired firefighter Katherine Crofton, who lives nearby, said she witnessed the start of the bloodshed from her porch.

"I saw him shoot this woman," Ms Crofton told the Buffalo News.

"She was just going into the store. And then he shot another woman. She was putting groceries into her car. I got down because I did not know if he was going to shoot me."

Braedyn Kephart and Shane Hill, both 20, had pulled into the car park just as the shooter was exiting.

They described him as a white male in his late teens or early 20s wearing camouflage, a black helmet and what appeared to be a rifle.

"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?" Mr Kephart said.

He said the offender dropped to his knees, "ripped off his helmet, dropped his gun, and was tackled by the police".

At the White House, press secretary Karine Jean-Pierre said President Joe Biden was receiving regular updates on the shooting and the investigation and had offered prayers with the first lady for the victims and their loved ones.

"The President has been briefed by his Homeland Security advisor on the horrific shooting in Buffalo, New York, this afternoon. He will continue to receive updates throughout the evening and tomorrow as further information develops," she said.

ABC/wires