Islamic Front spokesman Akram al-Halabi said the militant, known as Abu Khaled al-Suri, was killed today.
Al-Halabi said that an al-Qaeda breakaway group, the Islamic State in Iraq and the Levant, was suspected in the attack.
ISIL has been fighting with other rebel groups in northern Syria. It broke with al-Qaeda earlier this year.
According to al-Hababi, Abu Khaled al-Suri is the representative of al-Qaeda leader Ayman al-Zawahiri in Syria.
Al-Zawahiri appointed him to resolve fighting between rebels and ISIL.