A photo has emerged of the baby-faced teen accused of murdering four people in the first mass shooting of the US school year.

Fourteen-year-old Colt Gray surrendered when he was confronted by law enforcement during his deadly rampage at Apalachee High School in Winder, Georgia, on Wednesday (US time).

American news outlet 11 Alive published a photo of Gray taken from his 2022 school year book.

The picture reveals a smiling 12 or 13-year-old wearing a red Georgia Bulls T-shirt and thick necklace.

The Georgia Bureau of Investigations has reportedly charged Gray with four counts of felony murder, and more charges are expected.

He will be charged and tried as an adult, Chris Hosey, director of the Georgia Bureau of Investigation, said.

The boy’s aunt Annie Brown, told the Washington Post he had been struggling with mental health before the shooting and had been “begging for help from everybody around him.”

“The adults around him failed him,” she said, saying the child had a troubled home life that exacerbated his issues.

Two students and two teachers were killed and nine others wounded in the shooting, jolting the United States with the first mass campus shooting since the start of the school year.

The victims were identified as 14-year-old students Mason Schermerhorn and Christian Angulo, and teachers Richard Aspenwall, 39, and Christina Irimie, 53.

One of the victims was Richard Aspenwell, a maths teacher. Photo: Supplied 

Barrow County Sheriff Jud Smith said Colt was armed with an AR platform-style weapon, or semiautomatic rifle.

He was quickly confronted by deputies assigned to the school and immediately got on the ground and surrendered.

It later emerged Colt had been interviewed by law enforcement in 2023 over online threats about committing a school shooting.

The Federal Bureau of Investigation issued a statement revealing local law enforcement interviewed the subject in 2023 when he was 13 and his father in nearby Jackson County.

“The father stated he had hunting guns in the house, but the subject did not have unsupervised access to them. The subject denied making the threats online. Jackson County alerted local schools for continued monitoring of the subject,” the FBI said, adding that there was no probable cause for an arrest.

The shooting revived both the national debate about gun control and the outpouring of grief that follows in a country where such outbursts occur with some regularity.

People in Winder, a city of 18,000 some 80 kilometres north-east of Atlanta, gathered in a park for a prayer vigil later Wednesday night.

Some leaned on each other or bowed their heads in prayer, while others lit candles to honour the dead.

“We are all hurting. Because when something affects one of us it affects us all,” said Power Evans, a city councilman who addressed the gathering.

“I know that here tonight, all of are going to come together. We’re going to love on one another. … We’re all family. We’re all neighbours.”

Student Lyela Sayarath told CNN she was seated next to Gray in algebra class that morning when he left the room. He returned soon after and waited to be let back into the classroom, where doors locked automatically, she said.

“They almost let him in, but I’m pretty sure she (the teacher) saw that he had a gun and so she backed away,” Lyela said.

“Then he turned away and that’s when you hear, like, the first round of fire.”

Lyela said about 10 to 15 shots were fired “back to back” at the adjacent room when the boy couldn’t re-enter the maths class.

“I think he wanted to come to us first, to shoot [the] class,” she said.

When they heard the gunshots, students immediately dropped to the floor and huddled together. The teacher turned off the lights.

“As soon as they didn’t let him in, I kind of had a feeling it was going to happen, that it was him, and soon as you hear the gunshots you kind of know,” she told CNN.