A 20-pound window of a US Marine Corps helicopter fell off in mid-flight onto a school playing field Tuesday, slightly injuring a child on the Japanese island of Okinawa, CNN reported.
US Forces Japan said in a statement that the window of a CH-53 transport helicopter fell onto a sports field at an elementary school outside Marine Corps Air Station Futenma.
"We take this report extremely seriously and are investigating the cause of this incident in close coordination with local authorities," the statement said. "This is a regrettable incident and we apologize for any anxiety it has caused the community."
The child was not seriously injured, CNN reported.