A man works on an improvised weapon to be used by rebel fighters at a factory in the city of Aleppo, Syria's commercial capital, on July 7, 2013.
Free Syrian Army (FSA) fighters sit on the roof of a building in Deir al-Zor as one of them prepares a homemade bomb on Nov. 20.
A rebel fighter with a homemade weapon in the Bustan al-Qaser neighborhood of Aleppo on Oct. 15.
A fighter from the Tawhid Brigade, which operates under the FSA, prepares homemade rockets to be thrown toward the 80th Brigade base in Aleppo, controlled by forces loyal to Syria's President Bashar Assad, on Nov. 11.
An FSA fighter lights a homemade grenade before launching it on a catapult in Aleppo's Karm al-Jabal district on Oct. 28.
Two photos show FSA fighters using a catapult to launch a homemade bomb during clashes with pro-government soldiers in Aleppo on Oct. 15, 2012.
An FSA fighter makes improvised mortar shells at a weapons factory in Aleppo on Sept. 4.
A rebel holds up his hands, coated with an aluminum-based ingredient, after preparing homemade explosives in northern Syria in July, 2012.
A member of the Ansar Dimachk Brigade, part of the Asood Allah Brigade which operates under the FSA, uses an iPad during preparations to fire a homemade mortar in Jobar, Damascus, on Sept. 15.
A young man works to produce handmade missiles in a secret factory in Al-Bab, near Aleppo, on Jan. 19. Each day, nearly 50 missiles are assembled for the Abu Baker Brigade.
Rebel fighters fire a homemade weapon in the Bustan al-Qaser neighborhood of Aleppo on Oct. 15.
A rebel uses a control stick to activate the machinegun of Sham II, a homemade armored vehicle made by the rebels' Al-Ansar brigade, in Bishqatin, near Aleppo, on Dec. 8, 2012. Sham II is built from the chassis of a car and touted by rebels as "100 percent made in Syria."
FSA fighters spray paint on an improvised mortar shell at a weapons factory in Aleppo on Sept. 5.
Fighters from the Tawhid Brigade, which operates under the FSA, drag a rocket launcher near the 80th Brigade base in Aleppo on Nov. 13.
An FSA fighter throws a homemade mortar in Deir al-Zor on Oct. 10.
FSA fighters fire a homemade mortar from Maaret al-Naaman town towards the Wadi al-Deif military base in Idlib on Nov. 18.