Backup Dancer For Beyoncé, Rihanna Vanishes, Police ProbingBackup Dancer For Beyoncé, Rihanna Vanishes, Police ProbingNORTH BERGEN, N.J. (AP) — Police in New Jersey say they're investigating a report that a backup dancer who has performed with Beyoncé, Rihanna and Missy Elliott has gone missing.Associated PressAssociated Press