(Reuters)—At least 19 North Korean sailors were killed when a naval vessel sank during “combat duties” off the east coast last month, state media said, a rare admission by the impoverished and reclusive country.

South Korean media said the ship sank during a drill killing “scores”.

Photos released by North Korea’s KCNA state news agency showed leader Kim Jong Un laying flowers at the foot of a memorial to the dead, encircled by at least 19 graves emblazoned with the faces of the sailors.

“Submarine chaser No. 233 fell while performing combat duties in mid-October,” KCNA said.

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