The father of the 14-year-old boy suspected of shooting dead four people and injuring nine more in a Georgia school has been arrested.

State officials said Colin Gray knowingly allowed his son Colt to have the weapon he used in Wednesday’s attack.

Gray, 54, was charged with four counts of involuntary manslaughter, two counts of second-degree murder and eight counts of cruelty to children, the Georgia Bureau of Investigation (GBI) said.

“These charges stem from Mr Gray knowingly allowing his son Colt to possess a weapon,” Chris Hosey, director of the GBI, told a news conference.

Colt Gray has been charged with four counts of murder and officials have said he will be tried as an adult. He is due to appear in court by video camera on Friday morning.

Two 14-year-old students and two teachers were killed in the attack on the Apalachee High School in Winder, northeast of Atlanta, reviving a long-running US debate on gun control.

Investigators say the younger Gray used an “AR platform style weapon”, or semiautomatic rifle, to carry out the shooting.

It remained unclear exactly how the teenager came into possession of the weapon.

Citing unnamed sources, CNN reported that the gun, which it described as an AR 15-style assault rifle, had been bought for the teenager by his father as a holiday gift.

“The investigation into the shooting at Apalachee HS is still active [and] ongoing,” the GBI said in a post on social media platform X.

Parental responsibility

Officials identified the two students killed as Mason Schermerhorn and Christian Angulo. The two teachers were Richard Aspinwall, 39, and Cristina Irimie, 53. Nine people were injured, seven of them students. All are expected to make a full recovery.

Parental responsibility in mass shootings, particularly those carried out by minors, has come increasingly under the spotlight in recent months.

“How could you have an assault rifle, a weapon in a house, not locked up and knowing your kid knows where it is?” President Joe Biden told reporters on Thursday.

“You’ve got to hold parents accountable if they let their child have access to these guns.”

In April, the mother and father of a Michigan teen were sentenced to between 10 and 15 years in prison when a jury convicted them of manslaughter after their son shot and killed four classmates. It was believed to be the first time parents had been held legally responsible for their child’s actions in a school shooting.

Experts and gun safety advocates said the Michigan case was an important step in holding gun-owning parents more accountable for gun violence carried out by their children.

Studies by the US Department of Homeland Security have shown that about 75 percent of all school attackers got their weapons from home.

The United States has seen hundreds of shootings inside schools and colleges in the past two decades. The carnage has intensified the debate over gun laws and the US Constitution’s Second Amendment “to keep and bear arms”.