At least 10 people have been killed and three others injured in a mass shooting at a supermarket in the US city of Buffalo, New York state.
Police said the suspected gunman was taken into custody after the attack which is being investigated as “a racially-motivated hate crime”.
Buffalo Police Commissioner Joseph Gramaglia said that 11 of the 13 people who were shot were black.
“This was pure evil,” said Erie County Sheriff John Garcia in a news conference. “It was straight up racially-motivated hate crime from somebody outside of our community.”
New York Governor Kathy Hochul said: “It is my sincere hope that this individual, this white supremacist who just perpetrated a hate crime on an innocent community, will spend the rest of his days behind bars. And heaven help him in the next world as well.”
Court papers named the suspect as Payton Gendron, 18, of Conklin, New York. He was arraigned and charged with first-degree murder charges hours after the shooting, to which he pleaded not guilty.
Buffalo Mayor Byron Brown said the suspect “travelled hours” to the Tops Friendly Market in Jefferson Avenue, about 3 miles (5km) north of downtown Buffalo.
Investigators believe the man may have been live-streaming the shooting and are looking into whether he had posted a manifesto online.
The Buffalo News said the attack had been carried out by a gunman dressed in body armour and armed with a high-powered rifle.
Officials said the man entered the supermarket and opened fire, with witnesses having reported hearing dozens of shots being fired.
SWAT teams rushed to the scene.
Braedyn Kephart and Shane Hill, both 20, told the Associated Press they pulled into the car park just as the gunman was attempting to leave the scene.
They said he was a white male in his late teens or early twenties and wore a full camouflage outfit, a black helmet and carried 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 they saw him drop to his knees, adding: “He ripped off his helmet, dropped his gun, and was tackled by the police.”
Will G, an employee at the Tops supermarket, told the Buffalo News he walked into the refrigerated section to put milk on the shelves about three minutes before the shooting.
“I just heard shots. Shots and shots and shots,” he told the local paper. “It sounded like things were falling over.”
A law enforcement official on the scene told the newspaper: “It’s like walking onto a horror movie, but everything is real. It is Armageddon-like. It is so overwhelming.”
President Joe Biden said: “We grieve for the families of ten people whose lives were senselessly taken and everyone who is suffering the physical and emotional wounds of this horrific shooting.
“The First Lady and I are praying for the victims and their families, and hearts all across this country are with the people of Buffalo.”
He added: “We still need to learn more about the motivation for today’s shooting as law enforcement does its work, but we don’t need anything else to state a clear moral truth: A racially-motivated hate crime is abhorrent to the very fabric of this nation.
“Any act of domestic terrorism, including an act perpetrated in the name of a repugnant white nationalist ideology, is antithetical to everything we stand for in America. Hate must have no safe harbour. We must do everything in our power to end hate-fuelled domestic terrorism.