Did China just accidentally reveal one of North Korea’s most closely guarded state secrets?

In an innocuous-looking message, China’s state-run Global Times newspaper on Tuesday appeared to reveal the birth date of North Korean leader Kim Jong Un in a tweet by the outlet’s official Twitter account as the young dictator arrived in Beijing earlier in the day for his fourth meeting with Chinese President Xi Jinping.

“January 8 is #KimJongUn ‘s 35th birthday, which means he will celebrate his birthday during his January 7 to 10 visit to China,” the tweet said.

January 8 is #KimJongUn ‘s 35th birthday, which means he will celebrate his birthday during his January 7 to 10 visit to China. pic.twitter.com/78GMCKTO5l — Global Times (@globaltimesnews) January 8, 2019

While the birthdays of Kim’s grandfather and father, Kim Il Sung and Kim Jong Il, are already designated national holidays and are often marked with pomp and circumstance, including military parades, patriotic chants and oaths of loyalty to the leaders, his remains unknown in the North.

According to media reports, official North Korean calendars even marked Tuesday as a normal workday.

Observers say is likely due to his relative youth in a place where one’s age often dictates their levels of respect. Another possible reason, some have posited, is that organizing festivities in the wintertime would be inordinately costly. Yet another possibility is that it simply remains too early in his reign to do so. As the latest in the Kim family dynasty, the current leader ascended to the country’s top post in late 2011, leaving him with relatively few accomplishments and experiences to tout.

The closest that North Korea came to acknowledging his birthday was in 2014, when visiting basketball star Dennis Rodman sang “Happy Birthday” to him after an exhibition match in Pyongyang.

Highlighting just how sensitive the date is, viewers outside of North Korea were able to see video of Rodman’s performance, but domestic audiences were merely told that the former NBA player had “sung him a special song.”

Kim’s birth date was first revealed by Japanese national Kenji Fujimoto, Kim Jong Il’s sushi chef for 13 years. South Korea lists it as Jan. 8, but remains unclear on the exact year.