Three Japanese soldiers killed by shell explosion inside Type 10 tank

Three members of Japan’s Ground Self-Defense Force were killed Tuesday morning when a shell detonated inside a tank during a live-fire exercise at the Hijudai training area in Oita Prefecture, southwestern Japan.

The incident, one of the most serious training accidents to affect the GSDF in recent memory, also left a fourth soldier seriously wounded.

The explosion occurred at approximately 8:40 a.m. local time inside a Type 10 main battle tank. The three soldiers killed were identified as Sgt. 1st Class Kentaro Hamabe, 45, who served as the tank commander; Sgt. Shingo Takayama, 31, the tank’s gunner; and Sgt. Kozo Kanai, 30, assigned as a safety officer. All three were positioned inside the turret at the time of the blast. A fourth crew member — the tank’s driver, who was located in the hull — survived but sustained serious injuries and was transported to a hospital. No damage was reported outside the boundaries of the training range.

GSDF Chief of Staff Gen. Masayoshi Arai addressed the incident at a press conference following the accident, confirming that a 120-millimeter anti-tank shell exploded inside the tank’s turret. He did not elaborate publicly on what caused the premature detonation, and the circumstances surrounding the malfunction remain under investigation.

The Type 10 is Japan’s most advanced main battle tank, developed domestically by Mitsubishi Heavy Industries and fielded by the GSDF beginning in 2012. Lighter and more technologically sophisticated than its predecessor, the Type 90, the Type 10 was designed with Japan’s rugged terrain in mind and features a 120-millimeter smoothbore gun capable of firing standard NATO-compatible ammunition. The tank’s crew configuration places the commander, gunner, and loader — or in autoloader-equipped variants, the commander and gunner — within the turret, while the driver is positioned separately in the hull at the front of the vehicle. That physical separation between hull and turret likely explains why the driver survived while the three turret crew members did not.

Japan’s Self-Defense Forces have been undergoing a significant period of expansion and modernization under the country’s revised National Security Strategy, adopted in late 2022. Tokyo committed to doubling its defense budget over five years, with major investments directed toward ground force capability, long-range strike systems, and joint operational readiness. As the GSDF increases its training tempo in line with those priorities, Tuesday’s accident serves as a stark reminder of the dangers inherent in high-intensity live-fire training — even with the most modern equipment available.

The GSDF has not yet announced whether training operations at Hijudai will be suspended pending an investigation. The cause of the shell detonation inside the Type 10 turret remains the central question facing military investigators.