Could be a reaction to Qaddafi hiring mercenaries from African countries to be his hit men. I remember some of the earlier reporting from Libya stating some atrocities carried out by those groups against Libyans.
Libya has approx. 6 milion people, 25% of whom are Black.
Eastern tribes (the rebels) comprise no more than 20% of Libyan population. They have racist disposition towards all other Libyans.
No wonder NATO use that scum to destabilize Libya, Africa and ME.