BATON ROUGE — One student was arrested after a gun went off in a classroom at Istrouma High School on Wednesday morning, the Baton Rouge Police Department said.

Shortly before 10 a.m., a loud bang was heard from a classroom at the high school, an East Baton Rouge Parish School System spokesperson said. The school was then placed on lockdown while administrators and the School Drug Task Force conducted a thorough sweep of the building, during which they found a gun in a ceiling tile.

Two students were taken into custody shortly after the gun was found. Police said a high school student, 18-year-old Marcus Washington Jr., was arrested. He allegedly had the stolen gun, which was equipped with a machine gun conversion device, when it went off.

Washington Jr. was booked for carrying a firearm on school property, negligent carrying of a concealed, illegal use of weapons, possession of machine guns, and illegal possession of a stolen firearm. 

"Based on the preliminary investigation, we believe the weapon was accidentally discharged into the classroom ceiling," the school district said.

Superintendent LaMont Cole said that the two students, both boys, were not cooperating with investigators.

No one was injured, a spokesperson added.

School officials said that the student did not bring the weapon to cause harm to another student. An investigation is underway into how the student brought the gun onto campus.