Al Qaeda branches urge terrorists in Syria to unite

(CNN) – Terrorist group ISIS was originally a branch of al Qaeda in Iraq.

But main al Qaeda leadership cut ties in February, after ISIS supposedly disobeyed orders. Among the groups ISIS is fighting in Syria now is an al Qaeda affiliate called the al Nusra front.

But other al Qaeda branches, in an extraordinary move, are calling on these terrorist forces in Syria to take a hard look in the mirror, put aside their differences and focus on what's really important to them – hating and killing Americans.

CNN's Pamela Brown reports.