A U.S. F-16 fighter jet belonging to Misawa Air Base dumped two fuel tanks Tuesday evening before making an emergency landing at Aomori Airport in northeastern Japan, the Defense Ministry and local authorities said.

The emergency landing at around 6:10 p.m. prompted the closure of the airport's lone runway, affecting several domestic flights. Although there were no reports of injuries, the accident is likely to rekindle safety concerns among local residents due to similar instances of fuel dumping in recent years.

Aircraft believed to be a U.S. F-16 fighter jet belonging to Misawa Air Base, seen at Aomori Airport in northeastern Japan on Nov. 30, 2021.(Kyodo)

The 35th Fighter Wing of the Misawa base said an F-16 fighter jet experienced trouble during flight and its pilot jettisoned fuel tanks into an unpopulated area around Mt. Iwaki in Aomori Prefecture.

But contradicting the U.S. military's statement, at least one of the two fuel tanks was apparently dropped in a residential area, as local police spotted metal objects and liquid believed to be fuel on a road near a municipal government office.

Police sealed off the area amid potential hazards and the strong smell of fuel.

Metal objects dumped from a U.S. F-16 fighter jet belonging to Misawa Air Base are pictured in the morning on Dec. 1, 2021, in Fukaura, Aomori Prefecture. (Kyodo)

According to local authorities, the cause of the emergency landing remains unknown. It is also unclear when the airport will be able to open its runway, as the fighter jet is incapable of leaving.

A prefectural government official criticized the incident as something "that should not happen." The U.S. air combat unit said in a statement that it will conduct a thorough probe to find out the cause of the accident.

An official at Tohoku Defense Bureau said, "We heard that (the pilot) dumped fuel tanks to secure safety while making an emergency landing. It's not clear whether the fighter was engaged in training."

In 2015, an F-16 fighter jet dumped fuel tanks into the Sea of Japan off Aomori Prefecture, and another F-16 fighter ditched fuel tanks into a lake near the Misawa base in 2018.

The Misawa base houses both the U.S. military and Japan's Self-Defense Forces.