In the music business, sampling other artists' songs is relatively common practice, but it is usually done with permission.

Because of intellectual property rights, using another musician's work must be proceeded with caution and through the necessary legal channels.

This, however, was not the case with girl group TAHITI's recent university festival performance.

Recently the group used the intro from male idol group JYJ's song "Mission" for their performance at a college festival, and it was later revealed they had no permission to do so.

Talking with the event's MC after their stage performance, the TAHITI members said, "This intro is usually only specially used for our international performances, but we are using it for this college performance today."

JYJ fans then notified C-JeS Entertainment of the matter, and it was then revealed TAHITI and their agency Dream Star Entertainment did not have permission to use the clip from "Mission."

It was also discovered that the girl group had previously used the intro at a concert in Cambodia earlier this year and that the idea had come from an international concert rep.

According to Dream Star Entertainment, TAHITI's manager did not think to check before using the intro at other performances, including the recent university festival.

The agency also issued an apology to JYJ and C-JeS Entertainment saying, "We should have just used it once and left it at that. We didn't know, so we used it at the performance in Cambodia and again at the university festival."

The statement continued, "Had we known that the song belonged to JYJ, we would not have used it."

The performance and short apology have gained the attention of many netizens who have pointed out the unlikeliness of TAHITI's agency not knowing intro was part of JYJ's "Mission."

"Using it 'just once' doesn't mean it isn't illegal," remarked one online commenter.

Moreover, outraged JYJ fans have torn apart the statement for being insincere and illogical.

"They wouldn't have used it if they knew it was JYJ's? That means they would have continued using it if it belonged to some unknown artist," wrote one netizen. "You should be coming up with your own content for your performances instead of copying others."