The North Korean official publicly purged by Kim Jong-un was set up by his own wife and has since been executed, according to experts and the North Korean state news agency.
The state news agency KCNA called Jang Song-thaek, who had been Kim's uncle and top deputy, "despicable human scum" and "worse than a dog" in a release announcing his execution.
The news agency said the country was outraged by the allegations that Jang betrayed the trust of Kim Jong-un and his later father Kim Jong-il, referred to as "peerlessly great men."
"Against the backdrop of these shouts rocking the country, a special military tribunal... was held on December 12 against traitor for all ages Jang Song Thaek," KCNA reported in a story that was headlined "Traitor Jang Song Thaek Executed."
Jang's execution was announced as fresh details emerged about Kim's surprising public purging of his uncle from a top position which indicate it was a family affair with his aunt and brother, armed with a pistol, taking part in the arrests of ranking officials.
Analysts who study the secretive regime also fear that the arrest and execution of Jang, the man widely known to have been the real power behind Kim, signals a generational change for North Korea as well as period of upheaval.
Jang was arrested this week for corruption, acts of treachery, and womanizing with state TV airing humiliating photographs of him being dragged out of the Party Central Committee meeting by uniformed officers.
Jang had supported a smooth transition of power to a young Kim Jong-un, who was 28 at the time of Kim Jong-il's death in 2011. He is the uncle of Kim and husband of Kim Jong-Il's sister Kim Kyong-hee.
"What you have to understand is that the North Korean dynasty is run by an absolute blood-based hereditary mindset," pointed out Lee Yun-keol, the president of North Korea Strategic Information Service Center.
The purge drama was designed by Kim Kyong-hee, Jang's wife, and Kim Jong-un, Lee said. "She has openly expressed to the political bureau members that Jang's power line is a threat to the royal family so she took an obvious choice."
Lee claims that Kim Jong-un's older brother Kim Jong-chul personally directed the arrest of Jang's two closest aides last month.
"He was even armed with a gun when he took the General Guard Bureau soldiers to arrest and execute the men," Lee said.
Lee is a former North Korean soldier who fled to South Korea from the North in 2005 while working as a science researcher at the same General Guard Bureau's special unit in charge of Kim family's health. He communicates with former colleagues inside North Korea on a regular basis.
The arrest of Jang was remarkable for several reasons, observers said.
"That purge was surprisingly earlier than expected. Kim's been in power for less than two years and he does not yet have a strong political base in the party. North Korea is likely to be unstable for the time being," said Park Chang-kwon, senior research fellow at Korea Institute for Defense Analyses in Seoul.
"What is surprising is the dramatic and public nature of the purge. It's different from what has happened in the past," according to Daniel Pinkston, deputy project director for Northeast Asia at the International Crisis Group. "It might be a representation of Kim Jong-un's personal nature."
The most important significance of Jang's downfall is that it signals the beginning of a generation change of power. "Kim is young. He has a long way to go and this was an inevitable step to consolidate power around him with young and fresh generals," said Koh You-hwan, professor of North Korean studies at Dongguk University in Seoul.
North Korean state media has been rallying up "eternal loyalty" to its "great leader Kim Jong-un" on a daily basis this week. Four pages were devoted on Rodong Shimbun detailing public reaction to Jang's downfall.
"How dare someone like Jang tries to cover up the mighty sun!" said a director of a North Korean science research center. Other statements on the daily state newspaper included "I want to grab Jang by the neck and shove him down a boiling pot", "Jang is worse than an animal, full of immorality, and ungratefulness."
The South Korean media have also been reporting that a high-level North Korean official close to Jang had fled to China carrying confidential documents on North Korea's nuclear program and Kim Jong-un's private financial assets. Citing unidentified sources from North Korea, SBS TV, one of three main terrestrial channels in South Korea, claimed that the dissident is currently under custody of the South Korean government.
Jiyoung Sohn contributed to this report