Oh hell no! -- that's basically what Mya said to a fan who asked about the rumor that the singer had had decade-long affair with Jay Z.

On Thursday an eloquent fan wrote on the "Lady Marmalade" songstress' Instagram, "Heard you and Jay Z had an 11-year-affair. Are you his side chick or nah?"

Instead of turning the other cheek, Mya met the rumor head on, writing back, "Never did, never was, never will."

Mya added, "Illegitimate, thirsty sources with no facts and that's the