Suffolk County Police responded to Copiague Middle School, located on Great Neck Road, for a 911 call at around 6:45 a.m. Monday, March 10.
School administrators told officers that the student posted a picture of a gun on Instagram, police said.
Following an investigation, officers determined that the threat was not credible, police said. The boy was arrested on suspicion of making a threat of mass harm.
The student, who was not identified due to his age, will be arraigned in Suffolk County Family Court at a later date.
Click here to follow Daily Voice Roosevelt and receive free news updates.