The rapper was to headline the Easter Fest Rozay at Guyana National Stadium, but promoters announced that he would not perform mere hours before the gig.
Promoter Hits and Jams Entertainment said in a statement: "Rick Ross's management this evening informed management at Hits and Jams that the artist has suffered a medical emergency and has been ordered by his doctors not to travel.
"His management has given an undertaking that once he is cleared by doctors they are willing to work on an alternative date for the Guyana show."
Ross's cancellation comes six months after he suffered two seizures, causing him to axe several concerts last fall.
Two separate sources have offered conflicting explanations as to this latest cancellation, according to All Hip Hop.
One insider reportedly claimed that Ross had suffered a third seizure on Easter Sunday, while another informant alleged that a financial dispute actually led the musician to cancel.
A spokesperson for Ross has yet to offer any response to the cancellation.
In February, Ross's Florida home was the site of a murder investigation after a 40-year-old man was shot inside the musician's front gate. Ross was not named a suspect in the shooting.
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