On Tuesday, Kyle Rittenhouse grabbed an AR-15 style rifle and joined several other armed people in the streets of Kenosha, where businesses had been vandalised and buildings burned following a police shooting that left the 29-year-old black man Jacob Blake paralysed.
By the end of the night, prosecutors say, Rittenhouse had killed two people and severely wounded a third.
At a hearing on Friday, a judge postponed a decision on whether Rittenhouse, who is in custody in Illinois, should be returned to Wisconsin to face charges including first-degree intentional homicide that could land him in prison for the rest of his life.
To some, Rittenhouse is a domestic terrorist whose very presence with a rifle incited the protesters.
But to others – who have become frustrated with demonstrations and unrest across the country – he is seen as a hero who took up arms to help people who were left unprotected.
Lin Wood, a prominent Atlanta lawyer who is now part of a team representing Rittenhouse, said: “Kyle is an innocent boy who justifiably exercised his fundamental right of self-defence. In doing so, he likely saved his own life and possibly the lives of others.”
The protests in Kenosha are the latest to erupt during a reckoning over policing and racial injustice following the death of George Floyd at the hands of Minneapolis police earlier this year.
As they have in other cities, rallies devolved into violence and vandalism at some points, and the National Guard was called in.
The commander of the force said on Friday that more than 1,000 guard members have been deployed, and more are on the way.
Rittenhouse, once part of a youth cadet programme for aspiring police officers, can be seen on his Facebook page posing in a blue police uniform with a silver badge and broad-brimmed hat.
In other online photos and videos, he takes target practice and brandishes a rifle above the caption: “Blue Lives Matter.”
On Tuesday night, as Rittenhouse stood in front of a boarded-up building, he spoke to a reporter from the Daily Caller news site.
“People are getting injured and our job is to protect this business,” Rittenhouse said.
“And part of my job is to also help people. If there is somebody hurt, I’m running into harm’s way. That’s why I have my rifle.”
Rittenhouse and a friend armed themselves on Tuesday and made their way to a garage whose owner had put out a call for protection, according to a statement from John Pierce, a lawyer representing the teenager.
In the attorney’s description of events, Rittenhouse tried to offer medical help to injured people before he was “accosted by multiple rioters”, leading him to open fire.
The hashtag #FreeKyleRittenhouse has trended on Twitter, while a self-described Christian fundraising site says it has raised more than 100,000 US dollars (£75,000) for Rittenhouse’s defence, and a post including photos of the teenager cleaning up graffiti in Kenosha before the shooting was shared and liked thousands of times.
The night of the shootings, Rittenhouse is seen on video as a green-shirted figure running across a car park with a rifle followed by a man later identified as Joseph Rosenbaum, 36, according to a criminal complaint.
It adds that Mr Rosenbaum throws a plastic bag at Rittenhouse and misses, before five shots ring out and Mr Rosenbaum falls to the ground. He was later declared dead.
“I just killed somebody,” Rittenhouse says into his mobile phone, according to the complaint, before he starts running with several people giving chase.
“Beat him up,” one person in the crowd says, according to the complaint. Another yells: “Get him! Get that dude!”
Rittenhouse then trips and falls. One man holding a skateboard appears to try to grab the gun from Rittenhouse. A shot rings out, and the man, Anthony Huber, 26, staggers away. He also died.
In the scuffle, lasting just seconds, Rittenhouse shoots a third person armed with a handgun, according to the complaint. That man, Gaige Grosskreutz, 26, survived with a deep wound to his arm.
After the shootings, Rittenhouse can be seen walking toward police with his gun slung over his shoulder and his hands in the air.
Police officers in tactical vehicles then roll right past him.
The teenager later turned himself in in his hometown of Antioch, Illinois, according to Kenosha police chief Daniel Miskinis.
The police have faced questions about their response.
On Friday, Mr Miskinis described a chaotic scene to reporters and said that “there was nothing to suggest that this person (Rittenhouse) was involved in any criminal behaviour”.
He said it was not a lapse in judgment to fail to stop Rittenhouse and ask for identification to see if he was old enough to carry a weapon, given the number of people on the street, many of whom were wearing masks.
Wisconsin allows gun owners to openly carry in public, but a person under 18 cannot legally possess or carry a firearm unless that person is hunting or carrying out target practice with an adult or as part of the military.
