(CNN) -- One of the most secretive countries in the world seems to be putting a succession plan into place: North Korean leader Kim Jong Il promoted his youngest son to general.
Experts say that could be an indication that Kim Jong Un will succeed his father and his grandfather as leader of North Korea.
The outside world knows very little about Kim -- not even his age, which is apparently 27 or 28. But at least one person outside the reclusive communist state once considered Kim Jong Un his best friend.
Or at least he thinks so.
Joao Micaelo went to school in Switzerland with a boy he knew as Pak Un from 1998 to 2001. A teacher put them together at the same desk when the new student arrived, and they hit it off.
Then, one day Pak Un told Micaelo, "I am the son of the leader of North Korea." Micaelo "didn't believe him because ... it was a normal school," he told CNN Tuesday.
"Normally the children of people like this, they don't go to a normal school."
But having seen pictures of the apparent heir to Kim Jong Il, Micaelo thinks it's his high school friend. He remembered what his friend had told him years before.
"Then I said, "Okay, maybe it's true what he said to me,' " said Micaelo, who now lives in Bern, Switzerland, near the school he attended.
Local government officials in the town that's home to the Liebefeld School confirmed a student named Pak Un attended at the same time as Micaelo. The school declined to speak to CNN.
Micaelo remembers "Pak Un" being introduced as the son of the ambassador of North Korea. What is life like inside North Korea?
"He was a normal guy like me," Micaelo said, interested in sports, movies and computers. "He was competitive at sports. He didn't like to lose, like any of us. For him, basketball was everything," Micaelo said
"He played basketball, he had basketball games on his Playstation. The whole world for him was just basketball all the time," he said.
The North Korean, who spoke good enough German to be understood, was not outgoing, Micaelo said.
"He was very quiet and he didn't speak with anyone. Maybe it was because most of the people did not take the time to understand him," he said. "And he was not that type of guy who goes to another and says, 'Hello, how are you?' He was always quiet."
He didn't go out at night to parties or discos, but he and Micaelo sometimes talked about girls, his friend said. Micaelo went to his house many times, meeting people whom he thought were his friend's parents.
But they spoke English, not German, and because Micaelo didn't speak English well at the time, he didn't get to know them very well. But they struck him as "a normal family, like my family."
"Pak Un" didn't talk much about North Korea, Micaelo said. He hasn't seen his friend in years, since the North Korean moved home to go to a private school. But he'd like to see him again -- particularly if it didn't mean going to North Korea. Is there political change in the wind in North Korea?
"I would like to speak with him to remember old times, you know," Micaelo said.
"Because you know for me, he was also an important friend. He was my best friend at the time. I would like to see him again."
But, Micaelo said, he's not sure if now is the right time. "Just now I don't know if it's good to see him again. ... If he asked me to go visit him. I don't know if I go or not," he said.
Micaelo said he doesn't know what to expect from Kim as a leader. To read more on North Korea, go to CNN's special coverage
"I can just say what I know: Un, when he was 16, he was a good guy," Micaelo said. "So, I don't think he would do something bad. But I don't know what he's been like in the last nine years.
"I just knew him when he was 16 years old. He's been in a special school for this for nine years," he said. "Maybe he's another person."