Members of the media (left) gather at the entrance to the Hino basic firing range in the city of Gifu, Gifu prefecture, on June 14, 2023, where a shooting incident occurred with soldiers from Japan's Ground Self-Defense Force (SDF) at the training range. (PHOTO / AFP)

TOKYO - Japanese police arrested an 18-year-old soldier on Wednesday after he shot and killed two instructors and injured a third at a military firing range in central Japan, the country's defense ministry said.

The incident at about 9 am (24:00 GMT) in Gifu City was the first such fatal shooting at a Ground Self Defense Force (GSDF) firing range since 1984, GSDF Chief of Staff General Yasunori Morishita told reporters.

The three instructors, which public broadcaster NHK said included a man in his 50s and two in their 20s, were taken to hospital where two died, Morishita said.

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The alleged shooter, who is in police custody, joined the GSDF in April, he added.

This aerial photo shows the Ground Self Defense Force's base firing range in Gifu, central Japan, on June 14, 2023. (PHOTO / KYODO NEWS VIA AP)

"We will investigate the cause of the incident to ensure that it doesn't happen again," Morishita said at a media briefing.

Shootings are extremely rare in Japan, where gun ownership is tightly regulated, and anyone seeking to own a gun must go through rigorous background checks. Last year there were four gun deaths in Japan, according to the National Police Agency.

Among them was former prime minister Shinzo Abe, who was shot and killed with a homemade gun in July. The suspect, who has yet to be tried, had previously been a member of the Maritime SDF.

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The SDF deaths on Wednesday come after a military helicopter crashed with 10 crew members on board in the sea off an island in the southern prefecture of Okinawa in April.