People watch a TV news program showing North Korean leader Kim Jong Un, right, and Kim's uncle, Jang Song Thaek, circled in red, at the Seoul Railway Station in South Korea on Dec. 3. Ahn Young-joon/AP hide caption

itoggle caption Ahn Young-joon/AP

Before their split: North Korean leader Kim Jong Un, right, and his uncle, Jang Song Thaek, in February 2012. Earlier this month, Jang was executed. Kyodo/Landov hide caption

itoggle caption Kyodo/Landov

Before their split: North Korean leader Kim Jong Un, right, and his uncle, Jang Song Thaek, in February 2012. Earlier this month, Jang was executed. Kyodo/Landov hide caption

itoggle caption Kyodo/Landov

Jang Song Thaek, who was North Korea's second-most powerful official, was put to death this week. Kyodo/Landov hide caption

itoggle caption Kyodo/Landov

A still image taken from North Korea's state-run television footage and released Monday shows Jang Song Thaek being forcibly removed by uniformed personnel from a meeting of the Central Committee of the Workers' Party of Korea in Pyongyang. Yonhap/Reuters/Landov hide caption

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Former basketball star Dennis Rodman at Beijing Capital International Airport on Tuesday, before his flight to Pyongyang, North Korea. Petar Kujundzic /Reuters /Landov hide caption

itoggle caption Petar Kujundzic /Reuters /Landov

North Korean soldiers marched past statues of founder Kim Il Sung and his son, former leader Kim Jong Il, on Monday in Pyongyang. North Korea celebrated Kim Il Sung's 101st birthday. Kyodo /Landov hide caption

itoggle caption Kyodo /Landov

Secretary of State John Kerry shakes hands with Chinese President Xi Jinping before their meeting at the Great Hall of the People in Beijing. Kerry sought China's help in easing tensions on the Korean peninsula. Paul J. Richards/AFP/Getty Images hide caption

itoggle caption Paul J. Richards/AFP/Getty Images