DPRK top leader Kim Jong-un visits?the cemetery of navy soldiers who died during combat duty in October, in this undated photo released by Korean Central News Agency (KCNA) in Pyongyang on Nov 1, 2013. [Photo/CFP]

PYONGYANG - Dozens of navy sailors from the Democratic People's Republic of Korea were confirmed to have been killed when their warship sank during a drill last month, according to the official KCNA news agency.

The KCNA said DPRK top leader Kim Jong-un visited a cemetery for the officers and sailors last week, who lost their lives while "performing their combat duties".

Kim laid a wreath at the cemetery and paid a silent tribute to the fallen soldiers.

The sailors were on the submarine chaser No 233, which belonged to Navy Unit 790 of the Korean People's Army.

The report gave no details of the incident or the specific casualties, but TV footage of the Korean Central Television showed the cemetery had about 30 tombstones, on which was inscribed the date Oct 13.

A DPRK navy vessel sank last month near the country's eastern coastal city of Wonsan during a drill, according to South Korean media.