On Sunday, K-pop boy band BTS cancelled a concert series in Japan following health issues relating to two members of the group.

While fans were already in the hall for the first show of "2015 BTS Live, The Most Beautiful Moment in Life on stage, Japan Edition," BTS cancelled their performances due to Suga and V's deteriorating health. Other members performed a few songs to the audience while BTS's agency, Big Hit Entertainment, promised that there would be a full refund.

According to Big Hit, Suga and V's health situation may have been "a result of the intense dance moves throughout the performances."

BTS debuted with an intense hip-pop concept, and has been known for their powerful choreography.

Suga and V were set to prepare for the performance on Dec. 27, but went to a hospital after feeling ill and dizzy. Following a CT scan that showed "no particular problem" according to Big Hit's statement on Twitter, it was decided to cancel the concert to allow V and Suga time to recover.

Both Suga and V returned to South Korea to receive in-depth medical examination and treatment, if possible.

Because two members were unable to perform, it was decided that BTS would not be able to stage a show to the best of their ability.

Following the cancellation of both shows on Dec. 27 and 28, Big Hit apologized to fans and offered full refunds.

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