(A Free Syrian army fighter walks with his weapon through a hole in the wall in Aleppo’s Karm al-Jabal district, October 13, 2013. REUTERS/Saad Abobrahim)

Saudi Arabia’s grand mufti, the highest religious authority in the birthplace of Islam, has urged young Saudis to refrain from fighting in Syria.

The kingdom has backed the rebels battling President Bashar al-Assad, publicly calling on the world powers to “enable” Syrians to protect themselves, but is wary that fighters could return home ready to wage war on their own dynastic rulers.

Islamists in Saudi Arabia, who follow a puritanical version of Sunni Islam, denounce Assad and his administration as infidels because of their roots in the Alawite sect, an offshoot of Shi’ite Islam.

However, Sunni Muslim al Qaeda fighters led by Saudi-born Osama bin Laden attacked targets inside Saudi Arabia between 2003 and 2006, having gained experience fighting in Iraq, and before that in Afghanistan and elsewhere.