North Korea has officially confirmed the purging of its defense chief, admitting he was executed for offenses including talking back to country leader Kim Jong Un, complaining about his policies, and sleeping during a meeting.

The AP reported that South Korea's National Intelligence Service told lawmakers back in May that People's Armed Forces Minister Hyon Yong Chol had been executed at the command of Kim, but Hyon's disappearance was never addressed by the North's state media.

However, over the weekend, the country's official Korean Central News Agency named army general Pak Yong Sik as the armed forces minister in a dispatch about a meeting with a Lao military delegation, confirming Hyon's death, South Korean Unification Ministry spokesman Jeong Joon-Hee said.

Hyon, 66, who had served as the head of North Korea's military since 2012, was killed at a military camp in the capital Pyongyang on April 30 while hundreds of officials watched. At the time, Han Ki-Beom, deputy director of South Korea's National Intelligence Agency, told politicians that Hyon was killed by an anti-aircraft gun at Kang Kon Military Academy, a method reportedly reserved for senior officials who the leadership wishes to make examples of.

Hong Hyun-ik, chief researcher at the Sejong Institute, a security think tank based in Seoul, told local broadcaster YTN that the anti-artillery gun used would have left the body completely mutilated, the Daily Mail reported.

"Because there are several guns bound together, it would be hard to find the body after firing it once," he said. "It's really gruesome. What they did would have ripped all his flesh off, done in the manner of 'let's see what sort of punishment this is.'"

Kim Jong Un has ordered the executions of at least 70 North Korean officials since taking over the Communist country following the death of his dictator father Kim Jong Il in 2011.

In 2013, Kim had his uncle, Jang Song Thaek, executed for alleged treason. Jang was married to Kim Jong Il's sister and was once considered the second most powerful man in North Korea.

One anonymous source on North Korea told South Korean newspaper Munhwa Ilbo that Kim Jong Un's excessive demand of loyalty, frequest executions and shocking purges are part of his strategy to weaken the military's position in the state system.

Earlier in July, it was also reported that the manager of a terrapin farm had been executed on Kim's orders after several of the creatures died during a power cut.

"The gut-wrenching viciousness of such an act would make 'cruel and unusual punishment' sound like a gross understatement," the U.S. Committee for Human Rights in North Korea said, in a statement in April, referring to reports of previous executions. "Given reports of past executions this is tragic, but unfortunately plausible in the twisted world of Kim Jong Un's North Korea."