Police praised a passer-by who shot and killed a gunman in the midst of a shooting spree that killed three people and wounded two at a shopping centre in the US city of Indianapolis, Indiana.
Officials described the 22-year-old man, who was legally carrying a gun, as a “good Samaritan” for stopping the attacker almost as soon he opened fire on Sunday evening in the food court of the Greenwood Park Mall.
“This person saved lives tonight,” Greenwood Mayor Mark Myers said.
Greenwood Police Department chief Jim Ison said “the real hero of the day” was the citizen who was lawfully carrying a gun and stopped the shooter almost as soon as he began firing his weapon.
The killing of the gunman was quickly seized upon by supporters of America's Second Amendment that provides its citizens the right to bear arms.
“We will say it again: the only way to stop a bad guy with a gun is a good guy with a gun,” the NRA tweeted on Sunday night.
But the theory is contentious and, critics said, not supported by data.
The FBI designated 61 shootings last year as active shooter incidents, where at least one person was engaged in killing or attempting to kill others in a populated area.
Of the 61 incidents reported, two active shooters were killed by citizens, the agency said in a 2021 report. Fourteen were killed by law enforcement, 11 died by suicide and 30 were apprehended by police.
Last year's findings corroborate the little impact armed civilians have had in years before. Of the 345 active shooters designated from 2000-2019, four were killed by armed citizens, the FBI reported. In 2020, two of 42 active shooters were killed by armed citizens.
Recent cases, including the primary school massacre in Uvalde, Texas in May, show that even when heavily armed police are on the scene, the so-called “good guys” fail to stop the bloodshed.
At Tops Friendly Market in Buffalo, Aaron Salter Jr, a retired police officer who worked as a security guard, was killed when he confronted the suspected gunman, whose body armour protected him from the bullets. The gunman, Payton Gendron, returned fire, fatally injuring Salter.
Mr Ison on Sunday did not release the names of the victims, gunman or bystander. There were four female victims, including a girl, 12, and one male victim.
“Lives were lost today and I’m thinking about all the victims of this horrible incident, now and in the days and weeks to come,” Indiana governor Eric Holcomb said in a tweet.
A motive for the shooting is not yet known.
Sunday's shooting was the latest in a year that has rocked the US. More than 350 mass shootings have been reported in the country this year, data from the Gun Violence Archive shows.
Payton Gendron, who was 18 at the time of the attack at the Buffalo supermarket, faces 27 hate crime and federal arms offences. He is in state custody facing 10 counts of first-degree murder and 10 counts of second-degree murder.
He pleaded not guilty on Monday.
Mr Gendron could face life in prison or the death penalty if convicted on federal charges. Prosecutors must notify the court before trial whether they will seek the death penalty.
The arraignment comes as the penalty trial begins for the man who killed 17 people at a Parkland, Florida, secondary school in 2018.
Nikolas Cruz pleaded guilty in October to killing 14 students and three teachers at Marjorie Stoneman Douglas High School.
Jurors must decide if Cruz is to receive life in prison without parole or the death penalty.