The Atlantic Community Charter School in Galloway Township was put on a brief lockdown after a teacher reported what they believed to be a single gunshot.
Police have not been able to confirm gunshots.
Officers were called to the school on New York Road/Route 9 at 1:35 p.m.
The school was put on lockdown and police canvassed the school grounds and surrounding area and didn't find anything, Lt. Christopher McGinty said.
The lockdown was lifted at 2:30 p.m., but two officers did remain on scene to assist with dismissal.
