Subway commuters in Pyongyang, North Korea, read the news of Jang Song Taek's… (David Guttenfelder / Associated…)
BEIJING — It is North Korea's version of a youth revolution, and it's making a lot of people nervous.
At 30, Kim Jong Un may well be the world's youngest head of state. His brother, Kim Jong Chul, two years older, is best known as an avid Eric Clapton fan but is also said to keep an eye on the leader's security. And the youngest of the Swiss-educated siblings, 26-year-old sister Kim Yo Jong, is seen frequently as an aide-de-camp to the leader.
With Thursday's execution of their uncle, Jang Song Taek, and the purge of his cronies, this impatient new generation of the Kim family dynasty appears to be kicking out the adults. More executions are expected.
The developments also are worrying neighbors, including China, who wonder whether they can trust Kim Jong Un with the country's nuclear weapons and the flow of trade that keeps North Korea afloat.
"He had to get rid of the grumpy old men," said Andrei Lankov, a North Korea scholar based in Seoul. "He couldn't be a boss with subordinates who are twice his age, who don't understand him and don't take him seriously."
Kim's tactics in some ways are reminiscent of China's Cultural Revolution, launched by Mao Tse-tung in 1966, in which youthful Red Guards terrorized their teachers and other authority figures.
The 67-year-old Jang was for decades a trusted eminence grise, the interlocutor in an otherwise eccentric family. His wife was the youngest daughter of the current leader's grandfather and North Korea's founder, Kim Il Sung. She was also the sister of the young leader's father, Kim Jong Il.
Jang was appointed the de facto regent before Kim Jong Il died in December 2011, a job that included reining in youthful impulses — something the younger Kim clearly resented.
In a 2,700-word screed released Friday, Jang was accused of doing "serious harm to the youth movement in our country, being part of the group of renegades and traitors in the field of youth work bribed by enemies."
Just two years in power, Kim Jong Un has made a cult of youth the theme of his rule, investing the country's scarce resources in water slides, roller coasters and ski slopes.
The most notable foreign dignitary to visit Pyongyang, the capital, since he took over is the tattooed, body-pierced former NBA star Dennis Rodman, who is supposed to visit again next week.
Along with the charges of plotting a coup, the report by the official Korean Central News Agency detailed petty grievances that Kim clearly had been nursing for the last two years. Among them: When a monument was built to showcase a letter written by Kim to a unit of the People's Internal Security Forces, Jang directed that it be placed in a shady corner rather than in front of the building.
Jang also was accused of showing a lack of enthusiasm when Kim, while his father was leader, was promoted to vice chairman of the Central Military Commission. "He behaved so arrogantly and insolently, as unwillingly standing up from his seat and halfheartedly clapping," the report said.
Since his father died, Kim has fired five of the seven elderly statesmen who walked behind the car carrying the coffin in the funeral procession.
At least two other senior officials who reported to Jang have been executed: Ri Yong Ha and Jang Soo Kil. A defector group in Seoul reported that brother Kim Jong Chul personally held the pistol when the two were arrested because nobody else was brave enough to do it.
Although the story is likely to be apocryphal, it is indicative of the myth Kim is trying to create: he and his two siblings as heroic young warriors defending the Kim bloodline against interlopers.
"Kim Jong Un and Jong Chul often meet at the weekend to discuss matters. Jong Chul watches over his younger brother's security," defector Lee Yun-keol told the South Korean newspaper Chosun Ilbo.
The three siblings are the youngest known offspring of Kim Jong Il, born to his fourth wife, who died in 2004.
The three were packed off to be educated in Switzerland, since they were thought to be deep down the line of succession. Their older half-brother, Kim Jong Nam, was presumed to be the heir. But he lost power after an embarrassing effort to sneak into Tokyo's Disneyland in 2001 on a fake passport. He is now believed to be living in Macao.
The leader's younger sister appears to be playing a role similar to that of Jang's wife, Kim Kyong Hui, who as Kim Jong Il's only full sibling was constantly at his side.
More executions are anticipated as the purge continues. Unconfirmed reports from Seoul suggest that Kim might be going after another of his mentors: Ri Su Yong, who was appointed ambassador to Switzerland in 1988 and served as Kim's guardian while the boy was attending school in Bern.
Outside experts are concerned about the implications far beyond the North Korean power structure.