"Indeed, militants possess weapons such as ZU-23 [anti-aircraft gun] and others that are capable of hitting targets at the height of 4,000 meters, especially, such a big aircraft as Syrian Air Force's IL-76 military transport plane," Russian Defense Ministry spokesman Igor Konashenkov told RIA Novosti.
Maj. Gen. Igor Konashenkov confirmed that such attacks by terrorists were recorded in particular when the first batch of Russian-Syrian humanitarian aid was sent to Deir ez-Zor.
"It [the cargo delivery operation] is very risky. In most cases delivery is performed at night without any illumination."
"They [Syrian authorities] confirmed that the humanitarian aid is ditributed to people in need," Maj. Gen. Igor Konashenkov said.
Last week, Russia launched a humanitarian operation in Syria aimed at delivering supplies to civilians trapped in the regions of Syria controlled by the militants.
On January 15, a cargo plane of the Syrian Air Force using Rusian P-7 platforms airdropped a total of 50 tons worth of food supplies and basic necessities to the city of Deir ez-Zor.