The blast, which occurred on Wednesday morning, created a crater about 7 meters wide and 1 meter deep, forcing the cancellation of more than 80 flights. No injuries were reported.
Japan's defense ministry said the explosive was a 250-kilogram U.S.-made bomb from World War II. The incident scattered debris over a 200-meter radius, including onto the runway, according to the transport ministry's local office.
The explosion happened shortly after several domestic flights had used the taxiway. Footage from Japan's Civil Aviation College, which uses the facility for pilot training, captured a plume of dust and debris rising just two minutes after an aircraft passed nearby.
Miyazaki Airport, a former Imperial Japanese Navy air base, has a history of uncovering unexploded ordnance from World War II, with similar discoveries in 2011 and 2021.
