May 9—North Cobb High School was under a "code yellow" Tuesday afternoon following a threat, the Cobb County School District said.

"We discovered a threatening image that was air-dropped in one of our classrooms today. Due to this, our school is currently in Code Yellow," the district said. "Cobb County School District Police Department is actively investigating the issue now. Incidents like this are very serious, and the repercussions of engaging in such behavior is severe.

"We continue to be vigilant in securing our campuses and doing everything we can, to keep our students and staff safe."

The code yellow was the third investigation into threats at North Cobb High in recent days, according to the district. The first was a "possible threat to our school" which the district investigated over the weekend, and determined to be unfounded.

Then, Tuesday morning, a second rumor spread on social media. Police investigated and found that it was legal hunting activity in the area near the school, not a threat.

The third rumor originated with the threatening image distributed Tuesday afternoon. It is still being investigated.