General Kioumars Pourhashemi was killed in the attack on Thursday.
Iran has had an advisory mission in Syria sanctioned by Damascus to combat foreign-backed militants since 2011.
On Wednesday, fierce clashes between the Syrian Armed Forces and Al-Nusra Front terrorists continued in the countryside of Aleppo and Idlib, resulting in heavy losses for the militant groups, the Syrian Army announced in a statement.
According to Syrian sources, the fighting intensified early Wednesday morning, with military units responding to a large-scale attack by Al-Nusra terrorists and allied factions targeting civilian villages and military positions in clear violation of de-escalation agreements.
The Syrian Army’s General Command said its forces, supported by allied troops, successfully repelled the offensive and inflicted significant casualties on the attackers, both in personnel and equipment. The statement emphasized ongoing efforts to restore stability and normalcy to the affected areas.