Parents in Medford, Massachusetts are calling for the superintendent to resign after it was revealed a loaded gun magazine was found in the school's auditorium in December.
The gun magazine was found in McGlynn Middle School and wasn't reported to police or parents for seven weeks.
The Medford school district announced the discovery earlier this week.
Medford's mayor said the middle school's principal was put on paid leave for his alleged role in this, adding that the town was launching an independent investigation into the incident.
On Tuesday, Superintendent Roy Belson told NBC10 Boston he learned of the discovery in early January, and that he opted to not tell parents about it after being told it was an isolated incident.
The superintendent said the school's auditorium is frequently rented to outside groups, and that it is believed someone involved in one of the outside groups accidentally left it behind.
Belson said the Medford police chief was not directly informed of the discovery.
Parents voiced their frustration for more than four hours Thursday night in a fiery meeting with Belson and the school board.
Many in the crowd called on Belson to resign.
He is already planning on retiring in June.
The board cancelled school on Monday to allow teachers to discuss what to tell students about this, and the board is scheduled to meet next week to discuss if Belson should face punishment.