Jabhat al-Nusra, al-Qaeda's local branch in Syria, has sent Al Jazeera exclusive footage of what it said was a drone it shot down while it was flying over Aleppo, saying it was the first operation of its kind for the group.

The group said the government of President Bashar al-Assad has started deploying drones in its fight against the rebels, especially since opposition fighters escalated their assault on the northern city.

Cameras mounted on the unmanned, remote-controlled aircraft were being used by government troops to take aerial photos of rebel sites, Jabhat al-Nusra told Al Jazeera.

"We believe they are Iranian made and operate under the supervision of Iranian experts," a member of the group said.

Iran has been a staunch ally of the Syrian government and there have been several reports on the possibility that Iranian Revolutionary Guards are fighting alongside Assad's troops.

Jabhat al-Nusra, designated as a terrorist organisation by the US, is one of the most effective groups fighting the regime across Syria, but especially in Aleppo. It has carried out several deadly suicide bombings on military bases and government buildings.

The group declared its formation in early 2012, a year after the start of an uprising against Assad. The nearly three-year conflict has killed more than 120,000 people and left millions displaced.

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