According to the fighters, American helicopters dropped boxes of weapons in Yathrib and Balad districts in Iraq's Salahuddin Province on Friday.
The report comes as the Iraqi army and volunteer fighters appear to be gaining the upper hand and making significant gains against ISIL.
In October, a video showed the terrorist group capturing a bundle of U.S. weapons airdropped in the Syrian border town of Kobani.
The U.S. military admitted that it had dropped 28 bundles filled with grenades, mortar rounds and other supplies that were intended for Kurdish fighters.
The video showed masked terrorists inspecting the military equipment, which was airdropped in the areas controlled by ISIL near Kobani.
The U.S. Central Command said the airdrops -- including weapons, ammunition and medical supplies -- were "intended to enable continued resistance against ISIL attempts to take Kobani".
Back then, an ISIL-associated YouTube account posted a new video online entitled, "Weapons and munitions dropped by American planes and landed in the areas controlled by the Islamic State in Kobani”.
The video was also posted on the Twitter account of "a3maq news” which acts as an unofficial media arm of ISIL. The outfit has previously posted videos of ISIL militants firing American-made Howitzer cannons and seizing marijuana fields in Syria.
ISIL had broadly advertised its acquisition of a broad range of U.S.-made weapons during its rampage across Iraq. ISIL videos have showed its fighters driving U.S. tanks, MRAPs, Humvees.  
ISIL terrorists in the video were in possession of a rich bounty of American hand grenades, rounds for small rockets, and other supplies.
 The U.S. and its allies have been conducting airstrikes against ISIL in Iraq and Syria.
They said they were carrying out the airstrikes against the ISIL in both countries in order to curb their advance in the region. However, the air raids have so far failed to check the insurgents' military gains.
 An American commentator said the United States and the occupying regime of Israel are providing direct military aid to the ISIL terrorist group in Iraq and Syria.
Eric Draitser, the founder of stopimperialism.com, said in an interview with Press TV from New York that the U.S. military aircraft continue to drop weapons in the areas held by the terrorist group.
"ISIL continues its war with direct backing from the United States, Israel and a number of other powers,” Draitser said, adding that, "We have at least ten separate reports that the U.S. and its allies have been providing military aid in form of supposedly mistaken drops to the ISIL forces.”