Education minister, 63yrs old Kim Yong-Jin was shot dead after his bad sitting posture in parliament incurred the wrath of the North Korean dictator.
The slouching vice premier was interrogated and found to be an 'anti-revolutionary agitator' before his execution in July, a South Korean official said.
'Vice premier for education Kim Yong-Jin was executed', South Korea's unification ministry spokesman Jeong Joon-hee said.
'Kim Yong-Jin was denounced for his bad sitting posture when he was sitting below the rostrum,' he added, referring to North Korea's parliament.
Kim Jong-un was in the government meeting and was infuriated after Kim Yong-Jin sat in his chair 'with a bad attitude'.
Another South Korean official said the education official's poor posture was spotted at a meeting on June 29, when Kim Jong-un was named chairman of a new national defence department.
'The trouble for the minister began after he was seen sitting with bad attitude during a meeting of the People's Supreme Assembly,' the official told South Korean newspaper JoongAng Daily.
'He was later accused of being anti-revolutionary following a probe and a firing squad execution was carried out in July,' he added.