Gwinnett County school police traced an online threat against South Gwinnett High School to a student who is now under arrest and facing charges of making terroristic threats, officials announced Friday.

District spokesman Bernard Watson said police determined the threat posted Tuesday was a hoax and that students were not in danger. Still, Watson said, district procedure requires a serious response. Additional officers have been at the school this week for added security.

South Gwinnett Principal Rodney Jordan said in a letter to families Tuesday said the district was treating the situation with the “highest level of caution.” He said, “It is imperative that we exercise due diligence and thorough inquiry in our investigation.”

School police partnered with local, state and federal authorities to investigate the threat and digitally traced it to the student, Watson said.

The threat spawned concerns elsewhere in the district.

Jordan’s letter noted a “generic threat targeting multiple schools within the district.” Watson said police determined the original threat was made against South Gwinnett, circulated online and copied to name other Gwinnett schools.

Police have not provided identifying information about the student who was arrested. Watson was not able to say what school the student attends.

Watson said along with creating unnecessary fear, these threats lead some parents to remove students from school and miss class and put a strain on local law enforcement resources.

Watson said the district hopes all students realize that making threats is a serious offense. “A high school student made a poor decision and is now facing criminal charges,” Watson said.