North Korean leader Kim Jong-un's uncle Jang Song-thaek has likely been removed from power, a development that can cause a shift in power and heighten uncertainty within the country, the Seoul-based Yonhap News Agency reported Tuesday. The National Intelligence Service (NIS) made the assessment at a meeting with lawmakers and claimed multiple reliable sources have "independently confirmed" two of Jang's closest confidants were likely executed in public late last month, according to the report. The spy agency said that those accused were cited for corruption and activities that countered the stance of the ruling Workers' Party of Korea (WPK). The two were identified as Ri Ryong-ha and Jang Soo-kil, senior officials at the WPK's administration department. The NIS said Jang has not been seen since the executions. Jang's last appearance in Kim Jong-un's company was on October 10 at an event marking the 68th anniversary of the WPK's founding. "Such signs are an indication that Jang has probably been dismissed from all posts he held, although it is not known why he fell out of favor," a senior government source was quoted as saying. Intelligence indicated the North's military establishment has been informed of the executions and that the North Korean leader likely gave consent to such a move, the report said. Jang is married to the aunt of the North Korean leader. He holds the position of vice chairman of the powerful National Defense Commission and is widely regarded as the most influential figure in North Korea after Kim Jong-un. He is a member of the WPK's Political Bureau and the Central Military Commission as well holding other senior posts. Most experts credited the 77-year-old for playing a key role in Kim securing power after the sudden death of his father Kim Jong-il in late 2011 and views him as his young nephew's main protector. The incumbent leader is reportedly around 30 years old, with little experience running the country.