Update : Boy, 14, arrested after four killed in US school shooting

The Georgia Bureau of Investigation said those killed on Wednesday were two pupils and two teachers at Apalachee High School in Winder, Barrow County.

The boy, named as Colt Gray, a student at the school, was arrested by two officers on campus and was in custody, an official said. He will be tried as an adult.

Local sheriff Jud Smith described the attack as "pure evil".

Officers first recieved reports of a shooting at the school of around 1,900 pupils at around 10:20 local time (14:20 GMT).

"Within minutes law enforcement was on scene, as well as two school resource officers assigned to the school who immediately encountered the subject," the sheriff said in a news conference,BBC reported.

"The subject immediately surrendered. He gave up, got on the ground. And the officers took him into custody."

Officials said no motive had been identified and that law enforcement did not know of "any targets at this point".

They have not said what type of weapon was used, or how many bullets were fired.

The shooter was interviewed and spoke with investigators once in custody, Sheriff Smith said.

"This is going to take multiple days for us to get answers as to what happened and why this happened," he told reporters.

Dozens of police officers swiftly responded to the shooting at the school, which was placed on lockdown and cleared, with pupils taken to a nearby football stadium before being released to their families.

Lyela Sayarath, who was in the alleged shooter's class, told CNN that the suspect left the room at the beginning of their algebra lesson.

She said he came back and knocked on the door, which had locked automatically, but another student refused to let him in after noticing he had a gun.

Ms Sayarath told CNN the shooter then went to the classroom next door, where he began shooting.

Alexsandra Romero, a second-year pupil, said she was sitting in class when someone came barging in and shouted at students, warning them to get down.

"I can just remember my hands were shaking," she told the Atlanta Journal-Constitution. "I felt bad because everybody was crying, everybody was trying to find their siblings.

"I can still picture everything, like the blood, the shouting."

Marques Coleman, 14, said he saw the attacker holding a "big gun" just before the shooting began.

"I got up, I started running, he started shooting like, like 10 times. He shot at least 10 times," he told CBS News, the BBC's US partner.

"My teacher started barricading the door with desks," he said.

After standing up, the pupil said he saw "one of my classmates on the ground bleeding so bad", another girl shot in the leg and a friend shot in the stomach.

Georgia Governor Brian Kemp said on X, formerly Twitter, that he was "praying for the safety of those in our classrooms" and that he was directing "all available state resources".

Speaking at a campaign rally in New Hampshire, Democratic White House candidate candidate Vice-President Kamala Harris called the shooting "a senseless tragedy".

"It's just outrageous that every day in our country... that parents have to send their children to school worried about whether their child will come home alive.

"It doesn't have to be this way."

Republican White House candidate Donald Trump posted on his social media platform, Truth Social: "These cherished children were taken from us far too soon by a sick and deranged monster.”

Attorney General Merrick Garland, the top law enforcement official in the US, said federal agents were helping the investigation.

"I'm devastated for the families who have been affected by this terrible tragedy," he said.