A military helicopter accidentally dropped a box full of ammunition over a Texas elementary school Thursday mid-afternoon, leaving a gaping hole in the roof, according to officials.

The incident caused a portion of Parkland Elementary School to be without power, the Ysleta Independent School District said in a statement.

The mishap occurred after school had already been released, the statement read. Military police responded to the scene and an investigation is underway.

Local police retrieved the ammunition and will return it to Fort Bliss Military Police, KTSM reported, citing an official from the base.

The military base will reevaluate its current flight patterns to ensure a similar incident doesn’t happen in the future, a spokesperson told the outlet.

"I'm extremely sorry for any damage done to the neighboring elementary school, and I am grateful that no one was injured,” Col. Jay Hopkins, commander of the 1st Armored Division Combat Aviation Brigade, told the station. “The incident is under investigation.”