The US Defence Department announced that it is examining an Islamic State video appearing to show militants in control of US weapons intended for Syrian Kurdish fighters, the BBC reported.
Around 27 bundles containing small arms, ammunition and other weaponry were air dropped on Monday for militias defending the town of Kobani from Islamic State militants.
Pentagon spokesman Rear Admiral John Kirby said the vast majority ended up in the right hands.
“Kurdish forces control most of the town but the Islamic State remains a threat,” he explained.
Rear Admiral Kirby said the Islamic State had been kept at bay by a combination of US-led air strikes and the efforts of the Kurdish forces.
The British-based Syrian Observatory for Human Rights added that 30 terrorist fighters and 11 Kurdish defenders were killed on Tuesday and that the Islamists were bringing reinforcements.
On Monday, the US military said it had carried out air drops of weapons, ammunition and medical supplies to the Kurdish fighters.
It stated that 27 bundles had been dropped. A later statement said one bundle went astray but was destroyed to prevent it from falling into enemy hands, and that all the others were safely delivered.
But a video uploaded to the internet by a media group loyal to the Islamic State showed a cache of weapons, apparently dropped by the US, in militants’ hands.
Activists from the Syrian Observatory for Human Rights also said militants had seized one cache.
Rear Admiral Kirby said he could not confirm that the video was authentic.
“They are certainly of the kinds of material that was dropped… so it’s not out of the realm of the possible in that regard,” he stated. “When we have something definitive that we can provide in terms of an assessment on that we’ll do that.”