Russia's chief military officer says Syrian rebels have acquired portable air defense missiles, including U.S.-made Stinger missiles.

Gen. Nikolai Makarov, the chief of the military's General Staff, didn't say how many such missiles the rebels had and who supplied them. Makarov said Wednesday in remarks carried by Russian news agencies that some of the weapons could have been delivered by commercial airlines, but he didn't elaborate.

Russia has been Syrian President Bashar Assad's main supporter and ally, shielding him from U.N. sanctions over his crackdown on an uprising that began in March 2011. It also has continued to provide Syria with weapons despite Western protests.

A Syrian rebel told the AP in Turkey that the insurgents obtained dozens of shoulder-fired anti-aircraft missiles, but would not say who provided them.