TOKYO - Two members of Japan's Ground Self-Defense Force (GSDF), both in their 20s, died Monday after going missing during a training exercise in Oita prefecture, southwestern Japan, Kyodo News reported.

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The sergeants, assigned to a tank unit at Camp Kusu, were taking part in a reconnaissance infiltration drill at Hijudai Training Area when contact with them was lost. They were later found without vital signs and subsequently pronounced dead, according to the report.

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The GSDF said it was launching an investigation to determine circumstances surrounding the incident.