Four people were arrested Tuesday after a resource officer caught one of them with a loaded gun at a DeKalb County school, officials said.

Towers High School was placed on lockdown for several hours, the district told Channel 2 Action News.

Towers High School  (Credit: Channel 2 Action News)
icon to expand image

According to school officials, the officer noticed four trespassers Tuesday morning. One was in the school with the gun. The others were in the parking lot of the school, the district told Channel 2. Local police were notified and the suspects were arrested on trespassing charges.

The school was on lockdown until the end of the school day, the district said.

"An investigation is underway to determine how this incident occurred, if other persons were involved and how it can be prevented in the future," principal Vincent Denson said in a letter to parents.

Read more of the story here.