North Korean leader Kim Jong-Un has had two senior officials executed by an anti-aircraft gun, according to South Korean media.The conservative daily, the JoongAng Ilbo, reported on Tuesday that former agriculture minister Hwang Min and Ri Yong-jin, a senior official at the education ministry, were executed by an anti-aircraft gun at a military academy in Pyongyang earlier this month.Hwang was purportedly killed for making policy proposals that were seen as a direct threat to Kim’s leadership whereas Ri was said to have been executed for falling asleep during a meeting presided over by Kim, according to The Telegraph Further, according to Seoul’s unification ministry spokesperson Jeong Joon-Hee, two other senior officials had to undergo re-education sessions. One of them was Kim Yong-Chol -- a top official in charge of inter-Korean affairs.Since taking power after his father’s death in late 2011, North Korean leader Kim Jong-Un is believed to have executed or demoted a number of senior officials in what analysts say is an attempt to tighten his grip on power.South Korea's Yonhap news agency put the number of party officials executed during Kim Jong-Un's rule at over 100.The most notorious case was that of Kim's uncle and onetime No. 2 Jang Song-Thaek, who was executed for charges including treason and corruption in December 2013.In April 2015, it was reported that Kim had his defence minister Hyon Yong-Chol summarily executed with an anti-aircraft gun. Reports of the latest execution coincide with a series of high-profile defections from the North.North Korea's deputy ambassador to Britain has defected to the South with his family, the unification ministry said earlier this month. Thae Yong-Ho was driven by "disgust for the North Korean regime" and concerns for his family's future, it said. Twelve waitresses and their manager who had been working at a North Korea-themed restaurant in China also made headlines when they arrived in the South in April as the largest group defection for years. About 10 North Korean diplomats made it to the South in the first half of this year alone, Yonhap said, quoting informed sources.