A 14-year-old boy who allegedly shot dead two teachers and two teenage students at a school in the US state of Georgia was interviewed by the FBI last year over threats to commit an attack.

The FBI said it alerted local schools to monitor the then-13-year-old after tip-offs about online threats of a shooting at an unidentified location.

The boy and his father were interviewed by sheriff’s deputies at the time. The father said he had hunting guns in the house, but the teen had no unsupervised access to them, the FBI said on Thursday (AEST).

“The subject denied making the threats online. Jackson County alerted local schools for continued monitoring of the subject,” the FBI statement said.

“At that time, there was no probable cause for arrest or to take any additional law enforcement action on the local, state, or federal levels.”

The shooting at Apalachee High School in Winder, Georgia, on Thursday (AEST) was the first of the new school year in the US.

Nine people were also taken to hospitals with various injuries from gunshots, investigators said.

Two students & two teachers died in the shooting at Apalachee High School earlier today. They have been identified as:
⁃Mason Schermerhorn, age 14 (Student)
⁃Christian Angulo, age 14 (Student)
⁃Richard Aspenwall, age 39 (Teacher)
⁃Christina Irimie, age 53 (Teacher) https://t.co/qenBmWBcj2

— GA Bureau of Investigation (@GBI_GA) September 5, 2024

The suspect, identified as Colt Gray, 14, a student at the school, was in custody and would be charged and tried as an adult, Georgia Bureau of Investigation director Chris Hosey said.

Student Lyela Sayarath told CNN she was seated next to the suspect 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.

Lyela described Gray as very quiet and said he “never really talked” – only giving one-word responses.

“He was never there most times; either he just didn’t come to school or he would skip class,” she said.

“He fit the description of a shooter type.”

Local resident Gretchen Gierlach calls for an end to gun violence outside the school. Photo: Getty

Authorities said Gray was speaking with investigators, but they did not say if they knew what motivated him. They also did not say what type of gun was used in the shooting.

Barrow County Sheriff Jud Smith said the shooter was confronted by a deputy in the school and immediately got on the ground and surrendered.

Local TV stations broadcast images of parents lining up in cars on a road outside the school, hoping to be reunited with their children.

The school, which enrolled close to 1900 students in 2023, began classes for the year on August 1.

ABC News quoted another witness, student Sergio Caldera, as saying he was in chemistry class when he heard gunshots.

Caldera, 17, said his teacher opened the door and another teacher ran in to tell her to shut it “because there’s an active shooter”.

As students and teachers huddled in the classroom, someone pounded on the door and shouted repeatedly for it to be opened.

When the knocking stopped, Caldera heard more gunshots and screams. He said his class later evacuated to the school’s football field.

Families at a vigil after the shooting at Apalachee High School. Photo: Getty

The White House said President Joe Biden had been briefed on the shooting “and his administration will continue co-ordinating with federal, state and local officials as we receive more information.”

“Jill and I are mourning the deaths of those whose lives were cut short due to more senseless gun violence and thinking of all of the survivors whose lives are forever changed,” Biden said, calling on Republicans to work with Democrats to pass “common-sense gun safety legislation”.

Vice-President Kamala Harris, the Democratic nominee in November’s election, called the shooting a “senseless tragedy”.

“We’ve gotta stop it. We have to end this epidemic of gun violence,” Harris said at the start of a campaign event in New Hampshire.

Republican nominee Donald Trump wrote on social media that “Our hearts are with the victims and loved ones of those affected by the tragic event in Winder, GA. These cherished children were taken from us far too soon by a sick and deranged monster.”

The shooting was the first “planned attack” at a school this autumn, said David Riedman, who runs the K-12 School Shooting Database.

Apalachee students returned to school in August; many other students in the US return this week.

The US has had hundreds of shootings in schools and colleges in the past two decades, with the deadliest resulting in more than 30 deaths at Virginia Tech in 2007.

The carnage has intensified the pitched debate over gun laws and the US Constitution’s Second Amendment, which enshrines the right “to keep and bear arms”.