Apalachee High School in Winder, Georgia, received a threatening phone call Wednesday morning warning of shootings at five high schools, including Apalachee, before a gunman opened fire and killed at least four people.

CNN reported that Georgia law enforcement officials said the phone call to Apalachee High School warned that it would be the first target of five schools where shootings would occur. The officials added that they are still investigating the call and trying to find out who was behind it.

The shooting suspect, who is believed to be a 14-year-old male, is in police custody. The Georgia Bureau of Investigation (GBI) confirmed that four people were dead after the shooting and nine people were hospitalized. The GBI added that “reports of additional shootings at nearby schools are false.” CNN previously reported that as many as 30 people were injured in the shooting, but it was unclear how many people were suffering from gunshot wounds.

“We are asking for your patience … please let us get the facts that we need to make sure we get this right,” Barrow County Sheriff Jud Smith told reporters at a press conference shortly after the shooting suspect was detained. “This is going to take multiple days for us to get answers as to what happened and why this happened.”

One student told the Associated Press that he heard 10 gunshots and then heard a law enforcement officer yelling at someone, telling him to put his gun down. Police responded to calls of an active shooting at 10:23 a.m. ET and students were reunited with their parents beginning at around 11:30 a.m.

Apalachee High School is 45 miles east of Atlanta and has nearly 2,000 students.

President Joe Biden responded to the shooting, calling for gun bans and condemning Republicans.

“What should have been a joyous back-to-school season in Winder, Georgia, has now turned into another horrific reminder of how gun violence continues to tear our communities apart. Students across the country are learning how to duck and cover instead of how to read and write. We cannot continue to accept this as normal,” the president said.

“Republicans in Congress must finally say ‘enough is enough’ and work with Democrats to pass common-sense gun safety legislation,” he added.