An explosion Tuesday in a tank during a mililtary exercise in Japan killed three soldiers, Prime Minister Sanae Takaichi said.
The unusual accident at a training ground used by Japan's Self-Defence Forces in the southwestern Oita region saw "the tank's ammunition misfire inside," killing the three crew members on board and injuring another, Takaichi said.
The details of what caused the accident were under investigation.
"It is truly regrettable this happened," the prime minister wrote, offering her "heartfelt condolences".
