Janet Jackson was rushed to hospital last night, mere minutes before her show at Montreal's Bell Centre was scheduled to begin.

New reports say that the singer has since been released from Montreal's Royal Victoria Hospital, although there has been no confirmation as to what caused the visit.

"Yesterday evening she was checked into the Royal Victoria Hospital and left a couple of hours later," a hospital rep told People this afternoon.

According to a statement released by Jackson's PR reps, W&W, the superstar "got suddenly ill" during soundcheck, and the evening's performance was promptly called off.

According to multiple reports, fans had already taken their seats, and were getting ready to take in opening act LL Cool J when it was announced that they wouldn't be getting a firsthand peek at Jackson's Tron jumpsuit. The official announcement was made just five minutes before the show's start time, reports the Montreal Gazette.

"That's never happened before in Bell Centre history," a rep for concert promoter Gillett Entertainment Group told the paper.

The cause of Jackson's hospitalization is still unclear, but her reps say that she plans on bringing her Rock Withcu tour back to the city as soon as she can. Tickets for last night's show will be accepted for the make-up date and refunds are also available.

Jackson skipped a tour stop in Detroit last week citing "production constraints," and it's unclear whether she'll be well enough to play her next show, which is scheduled for Wednesday night in Boston.

News of her hospitalization comes just one night after the icon blew away the crowd at Toronto's Air Canada Centre with a 2-hour set packed with old-school hits, pyro blasts, break-neck choreography -- and even some NSFW groping of one lucky fan.

Which leads us to wonder, do you think she got mono from this guy?

Some sources have begun to speculate on the cause of Jackson's hospital visit. MTV News brought up Jackson's spotty bill of health this year, noting that the star missed her April Saturday Night Live gig due to a bad case of bronchitis. Added People, Jackson has complained of fatigue during this tour, which kicked off Sept. 10 in Vancouver. "A 42-year-old body can't handle what a 22-year-old body can," a friend of Jackson's bf, Jermaine Dupri told the magazine. "I can tell you that she's definitely tired. It was probably exhaustion. She is doing back-to-back, three-hour shows, and her body isn't the same as it used to be."

However, sources close to the Jackson and Dupri say that they doubt the singer is suffering from anything too serious. Dupri was spotted out partying in New York City last night, and says People's source, "If [Janet's condition] was more serious he would've rushed to her side."

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