janet jacksonJanet Jackson has postponed her next two concert dates after falling ill on Monday.

The star was rushed to the Royal Victoria Hospital in Montreal on Monday evening after getting “suddenly ill” at a sound check for that evening’s show in the city. No details were released about the nature of the illness but a spokesperson for the medical facility has confirmed that she was held for monitoring for a couple of hours before being released early on Tuesday.

Janet’s own spokesperson has now confirmed that the singer’s scheduled shows in Boston tonight, and in Philadelphia tomorrow night, have both been postponed until further notice. The North American Rock Witchu tour will resume in North Carolina on Saturday.

A source close to Janet’s boyfriend Jermaine Dupri told People magazine that it was “probably exhaustion” that hospitalised the singer: “A 42-year-old body can’t handle what a 22-year-old body can.

“I can tell you that she’s definitely tired. She is doing back-to-back, three-hour shows, and her body isn’t the same as it used to be.”

The source added that Jermaine spent Monday night partying in New York, a sign that there was nothing to worry about: “If [Janet’s condition] was more serious he would’ve rushed to her side.”