Ansar al-Sharia branch in Derna escaped an assassination attempt on Sunday (April 14th).
Sofian Ben Qumu (aka Abou Fares) was not hurt in the attack near Ras al-Hilal, between al-Bayda and Derna, Ansar al-Sharia spokesperson Youssef al-Jahani said.
Satellite channel Al-Hurra, however, said Qumu had been wounded in his shoulder.
Immediately after the shooting, Ansar al-Sharia militiamen surrounded their leader's home.
A security source speculated to AFP that a tribe that had accused the militia chief of killing one of its members last week was behind the ambush.
Ben Qumu led rebel forces in Derna during the revolution. He fought alongside al-Qaeda in Afghanistan before being detained in 2004 by the Pakistani authorities.
He is suspected of involvement in the September 2012 killing of US Ambassador Christopher Stevens and other Americans in Benghazi.
The failed assassination came five days after Ansar al-Sharia commander Yahya Abdel Sayed was murdered in Sirte.
The assassination attempt "might have been related to revenge or part of the post-revolution repercussions", Benghazi University lecturer Ahmed Youssef, said.
Reasons for the attack could include "personal revenge or political agenda of members of groups or movements described as Islamist".
Former Abu Slim prisoner Jamal Aziz al-Shaari was running Derna, Ansar al-Sharia spokesperson Youssef al-Jahani noted, but denied that there were clashes between Ben Qumu and the family.
"This is part of conflicts among radical groups," blogger Salim al-Ragie said on his Facebook page. "Salafist groups, most of which use takfir as a basis for their political ideology and the establishment of their Islamic emirate, have such a history."
"With the proponents of exclusionist ideology and radicals, everything is possible," government employee Munira Saleh said. "I advise them to benefit from specialised scholars and to learn the true meaning of religion and differences between sects. Our scholars must respond to Ben Qumu and his likes."
By Essam Mohamed in Tripoli for Magharebia – 17/04/13