(By Estera Popowska)

According to reports from South Korea, North Korea has publicly executed the country's defense minister accused of treason, CNN reported Wednesday.

Hyon Yong Chol was killed by fire from an anti-aircraft gun at a military school in front of hundreds of people in Pyongyang; the South Korean Intelligence Agency was reported to have told parliament members in a closed-door session.

Hyon was executed because he expressed discontent towards leader Kim Jong Un, and failed to follow Kim's orders on several occasions, according to Kim Gwang-lim, chairman of the National Assembly Intelligence Committee and a lawmaker with the Saenuri Party who attended the briefing.

CNN says the timing of Hyon's execution is unclear. Reports suggest he was killed "around April 30." The last mention of Hyon in North Korean state media was on Wednesday, April 29, when he was reported to have attended a performance of the Moranbong Band at the People's Palace of Culture, earlier that week.

Lawmaker Kim Gwang-lim said the South Korean spy agency said that Hyon was executed without trial within two to three days of being arrested. If the dates are correct, they suggest Hyon's fall from grace was swift and decisive.

Just last month, Hyon led a North Korean delegation to Moscow for a seminar on global security. North Korea leader, Kim himself had been scheduled to go to mark Victory Day commemorations on May 9. However, in late Aoril Russian officials announced that he had pulled out to attend to "domestic issues" at home.

According to reports, no single incident was said to have led to Hyon's arrest and execution, although Kim Gwang-lim said, along with general neglect of duty, Hyon was seen nodding off during a meeting organized by Kim Jong Un.

A spokesman for South Korea's Unification Ministry reportedly said the government considered the execution to be another display of "fear politics" in North Korea, according to CNN.

"Our government views that the purge is promoting the solidification of the only monolithic leadership of Kim Jong Un by creating atmosphere of fear," said Lim Byeong-cheol (CNN)