A Japan Maritime Self-Defense Force rescue boat on Thursday retrieved the pilot of a U.S. Marine Corps F/A-18 that crashed into the Pacific off western Japan the previous day, according to the Defense Ministry.

The condition of the pilot, who is set to be sent to the Marines' Air Station Iwakuni in Yamaguchi Prefecture, has not been immediately revealed.

The fighter jet stationed at the U.S. Iwakuni base went down around 6:44 p.m. Wednesday about 130 kilometers south of the city of Kochi in Kochi Prefecture.

The pilot ejected from the aircraft, and search and rescue efforts by the U.S. military in coordination with the MSDF and the Air Self-Defense Force were expanded to a greater radius, according to the Marine Corps.

The area is a designated training zone for the U.S. military.

"The incident was very regrettable. We want to request that the government ask the U.S. side to clarify the cause of the accident and come up with preventive measures," Kochi Gov. Masanao Ozaki told reporters earlier in the day.

The governor suggested he would call for a suspension of low-altitude training flights over Shikoku, which has four prefectures including Kochi, by the U.S. military until the cause of the accident is clear.

"We hope (the U.S. military) will allay local anxiety by making safety the first priority in operating military aircraft," Yamaguchi Gov. Tsugumasa Muraoka told reporters.