Stand-up comedy is a tricky business. It can be especially brutal when you have a tough crowd, and it doesn't get any tougher than the world's most closed-off, paranoid, dirt-poor, brutal dictatorship: North Korea. While comedians in the West can get booed or heckled off-stage for offensive material, one North Korean funny girl was sentenced to an indefinite period of “hard labor” at a coal mine after a “slip of the tongue” during a set last month.

Sources inside North Korea reported to Radio Free Asia that Lee Choon Hong, a locally famous comedian known for doing impressions and satirizing aspects of North Korean society, got herself into trouble while performing for workers in southeastern Kangwon province when she mentioned some “sensitive issues.”

“Lee Choon Hong had a slip of the tongue while giving a performance for the workers at the Sep’o reclamation project site,” an unnamed source said. Lee was among a troupe of several entertainers that were hand-picked to perform at the sprawling 150,000-acre Sep’o project site, an agricultural project started by the recluse nation’s new leader, Kim Jong-Un. For her unspecified "slip," Lee was “sent to the city of Sunchon in South Pyongan province to carry out reform work at the Jikdong Youth Coal Mine,” the source added.

The source wasn’t clear what specific mistake or joke prompted Lee’s punishment but did say she was interrupted in the middle of her performance and sent to the mine immediately, with no chance to return home first or say goodbyes to family members.

This could be Lee's second strike. “It's already the second time Lee has been forced to undergo reform work. She had suffered this embarrassment once in the mid-2000s for misspeaking,” the source said. A former high-ranking official from Pyongyang who has since defected to the South said he knew Lee well, confirming that she had been assigned to hard labor before. He first became familiar with Lee after she was recruited from North Korea’s propaganda group of a military unit to be part of something called the “Entourage of Delight,” which was essentially a tour of performers selected by late leader Kim Jong Il.

This time Lee has to be “extra careful about her every move,” the source said, explaining that she will be doing labor over a trial period. This type of punishment is often given to officials who have made inappropriate remarks about the leadership or the regime in general, and usually endure the punishment for about six months before being released.