Former Cosatu general secretary Zwelinzima Vavi and EFF leader Julius Malema are plotting to overthr.
This comes after a new incident in which nude pictures of socialite Khanyi Mbau and her ex-boyfriend Theunis Crous were posted on the site.
Mbau claimed in a tweet that the seven nude pictures of her in different suggestive poses were posted by Crous to "destroy" her.
Crous and his wife Primrose have denied this, but called the pictures "distasteful" in a tweet.
The pictures of Mbau were posted on Sunday afternoon and a picture of Crous, lying on his back holding his private parts, were posted shortly afterwards.
The pictures were re-tweeted by large numbers of users.
In one picture Mbau is crouched in the shower with her back to the camera and her arms spread out while in an even more provocative one she is standing on a bed with one leg up.
In September last year, a different set of steamy pictures of Mbau made it onto Twitter and Facebook - no one owned up to them either.
Media lawyer Okyerebea Ampofo-Anti said the people responsible could be sued for breaching Mbau and Crous's rights to privacy.
She said that if the matter was taken to a civil court, the culprit could be liable to pay damages.
FPB spokesman Mlimandlela Ndamase said they would speak to the police to see if they could help with the investigations.
Mbau failed to respond to a request for comment yesterday.