According to our insider, the bad blood started at Clive Davis' Grammy party a few months ago. At the party, Rihanna supposedly got a little too close with Bow Wow, Ciara's ex. Tells our insider, "The whole thing is really silly, because Ciara didn't even want [Bow Wow] at that time. She's just angry 'cause she just thinks Rihanna was being disrespectful."
Insiders say the feud may be more about jealousy than anything else.
Last week, Ciara gave her dancers an ultimatum when it comes to Rihanna. When the Bajan beauty's song Umbrella was played during a dance rehearsal, Ciara nearly lost it. "Ciara spazzed out ... She stopped the session and told everyone that the next time someone played a song by 'that no-talent girl', they'd be fired."