TVXQ vocalist Jung "U-Know" Yunho's emotional outburst onstage at a Tokyo Dome performance on Thursday was more than mere nostalgia for the 10-year anniversary of his group's Japanese debut.

"Although we can't hold concert tours for a while, we promise to come back," Yunho told the crowd, with tears streaming down his face, according to the Korean entertainment publication DBSK Sleepless Knights.

On Thursday, representatives from the 30-year-old pop star's record label, SM Entertainment, announced that Yunho will report for his 21 to 24 months of mandatory service in the South Korean army this year (the length of mandatory enrollment changes by several months depending on which branch of the military the soldier serves in).

But the SM reps stopped short of specifying exactly when the TXXQ singer would be reporting for duty.

"It's true Yunho is planned to enlist as an active duty soldier this year, but the specific time period has not yet been decided on," the statement read. "As he does have to go this year when looking at his age, it seems that's why he said that at the concert. Timing wise, it was their last tour of Japan before enlistment."

All eligible male South Korean citizens between the ages of 18 and 35 currently must sign up for the roughly two years of required army service or face jail time.

On the Korean entertainment website allkpop, TVXQ fans left hundreds of comments expressing their grief and frustration at the group's impending hiatus.

"I really don't want him to leave for two years," wrote a fan identified as EXO Lover 20040506. "I'm really crying, for real! I will really miss him a lot, but I will also be waiting for him. Yunho...I love you so much."

K-popper Ctg Col seemed to get at the core of what many might be thinking regarding the status of the two-man group.

"I wish him success while he's serving, but two years without TVXQ music?" the fan asked. "Changmin please [enlist] this year too, so that it's not four years without TVXQ."

Currently there have been no official reports regarding the enlistment of Yunho's bandmate. Though back in September, according to a post on the blogging website BlogSpot, the sister of a TVXQ fan who ran into Max Changmin in Rome, Italy claimed the singer told her it was his "last time" on vacation before joining the army.

Though it has yet to be announced which of the six branches of the military Yunho will serve in, the climate is probably not as hospitable to celebrities as it was a few year ago, when high-level stars were able to serve in a division called the Promotional Support Brigade, forgoing the military duty for a nonstop series of concerts and events aimed at boosting the morale of other soldiers.

All of this came to an end in 2013, when a film crew from the South Korean TV news program "Scene 21" filmed K-pop stars Sangchu from the group Mighty Mouth and Se7en entering a massage parlor known for providing erotic services. Other members of the division could be seen wandering the streets after curfew out of uniform, using personal cellphones and purchasing alcohol at 2 a.m. following an army-sanctioned concert.

The footage and the resulting public outcry in South Korea that it caused, led to Sangchu and Se7en receiving a 10-day sentence in military jail and the elimination of the Promotional Support Brigade.

Despite the SM statement on Yunho's enlistment, reportedly prompted by rumors surfacing in the Japanese media, TVXQ will presumably continue their performance schedule as planned.

The group is slated to perform in Los Angeles on May 2, as part of the Korea Times Music Festival.