The father of the 14-year-old boy suspected of killing four people during a shooting at Apalachee High School in Winder, Georgia, was arrested Thursday and charged with murder for allegedly allowing his son to have access to a weapon. 

The Georgia Bureau of Investigation (GBI) announced that the father had been charged with four counts of involuntary manslaughter, two counts of second degree murder, and eight counts of cruelty to children. 

GBI Director Chris Hosey said that the charges stemmed from the father “knowingly allowing his son” to “possess a weapon” but did not provide any further details. 

The suspected attacker, who will not be named per Daily Wire policy, has been charged with four felony counts of murder and is expected to be tried as an adult. 

Those killed in the mass shooting were 14-year-old students Mason Schermerhorn and Christian Angulo and math teachers Richard Aspinwall, 39, and Christina Irimie, 53. Nine others were injured in the shooting, which was stopped by a school resource officer who confronted the attacker. 

Earlier this year, the parents of a teenager who shot and killed four students at a school in Oxford, Michigan, were sentenced to 10 to 15 years in prison, the first time in history parents have been convicted over a mass shooting committed by their child. 

“This is a time for all of us as a community and a state to come together and remain vigilant,” Hosey said at a press conference on Thursday. “Students must be supported and encouraged here in this community and across this state to contact a member of their school faculty with any and all concerns of suspicious activity that they may see.” 

In an update on its investigation into the attack, GBI said that there had been reports of other students making threats against schools throughout the state and that police had made arrests in each instance. 

Barrow County Sheriff Jud Smith announced on Thursday that the nine injured during the attack are all expected to fully recover, though several are still hospitalized. 

“A young person brought a gun into a school and committed an evil act and he took lives and he injured many other people — not only physically but mentally,” he said. 

The FBI acknowledged on Wednesday night that it had received tips last year about the suspected shooter but did not have probable cause to make an arrest.