What a day for Janet Jackson! Although the singer is on a North American concert tour, she had no other choice but to cancel one of her shows, as she “got suddenly ill,” her publicists have announced.

The King of Pop’s sister was performing a sound check in Montreal on Monday when she suddenly felt out of shape and, thus, was immediately transported to an unnamed hospital. A statement released by W&W Public Relations did not give any details about Janet Jackson’s condition, but it did explain that the star was hoping to set another date for the Montreal gig.

The nature of her illness remains unknown and it has not been disclosed whether the 42-year-old singer had already been in poor health.

Last week, Janet Jackson announced that she would leave Island Def Jam Records after only 14 months. “Discipline,” the first album that the singer released with the record label, has only sold 415,000 copies in the United States since September, although it debuted at No. 1 in the album chart.

Janet Jackson’s North American tour kicked off on September 10 in Vancouver and is scheduled to continue in Boston, Philadelphia, Greensboro and Atlanta, among other cities. However, this is not the first time during the tour when the singer cancels a gig. Last Friday, Janet Jackson cancelled a concert in Detroit citing “production constraints.”