SEOUL: A major accident occurred at the launch ceremony for a new North Korean naval destroyer, state media reported on Thursday, with leader Kim Jong Un calling the mishap a `criminal act`.

At a ceremony to launch a new 5,000-ton vessel in the eastern port city of Chongjin on Wednesday `a serious accident occurred`, the official Korean Central News Agency (KCNA) said.

South Korea`s military said North Korea also fired `multiple unidentified cruise missiles` on Thursday, which were detected near the North`s South Hamgyong province after being `fired toward the East Sea`, also known as the Sea of Japan.

Blaming `inexperienced command and operational carelessness` for the destroyer`s botched launch which was observed by Kim KCNA said there was a mishap which left `some sections of the warship`s bottom crushed`. It said the accident managed to `destroy the balance of the warship`.

Kim watched the entire incident and declared it a `criminal act caused by absolute carelessness`, warning it `could not be tolerated`. He said the `irresponsible errors` of officials responsible would be `dealt with at the plenary meeting of the Party Central Committee to be convened next month`.

South Korea`s military said US and Seoul intelligence authorities assess that North Korea`s `side-launch attempt` of the ship failed.-AFP