Al-Nusra Front has declared war on the Islamic State in Iraq and Syria (ISIS). Abu Mohammed al-Golani gave ISIS five days to provide proof of its innocence regarding the killing of Abu Khaled al-Souri along with an ultimatum: either stop the fighting, withdraw apostasy edicts and return to the community or face a war, even in Iraq. Now all eyes are on the two groups as a violent confrontation might breakout between them at any minute.
http://english.al-akhbar.com/content/syria-al-nusra-front-declares-war-isis