Kim Jong-un ordered the execution of two high-ranking officials by anti-aircraft gun over fears that the dictator is preparing another purge against his people.
Ri Yong Jin, a senior official at the education ministry, was sentenced to death after he fell asleep in a meeting being addressed by Kim.
After accidentally dozing off, Ri was taken into custody and interrogated where security agents found evidence of his disloyalty and disrespect towards Kim.
According to South Korean newspaper Joongang Ilbo, Hwang Min, a former agriculture minister was also sentenced to death.
Hwang's crime, according to the South Korean media, was to have developed a number of ideas to improve agricultural production.
These ideas were seen by the regime as an attempt to undermine Kim.
Both men were executed by an anti-aircraft gun at a military academy in Pyongyang.
The North Korean regime is especially paranoid in recent weeks after a senior offiicial at the London embassy defected to South Korea along with his wife and children.
North Korea rarely announces purges or executions, although state media confirmed execution of Kim's uncle and the man widely considered the second most powerful man in the country, Jang Song Thaek, in 2012 for factionalism and crimes damaging to the economy.
A former defence minister, Hyun Yong Chol, is also believed to have been executed last year for treason, according to the South's spy agency.
The JoongAng Ilbo said the two men were executed by anti-aircraft gun at a military academy in Pyongyang.