WARNING: This post contains graphic details. Discretion is advised.
The U.S. government is looking for more information as to whether a Syrian opposition group it supported was behind the beheading of a young boy.
Video emerged Tuesday of purported opposition fighters severing the head of a captive Palestinian boy, alleged to be a fighter with a pro-government Palestinian group based near the northern city of Aleppo.
READ MORE: Syrian rebel group accused of beheading child on video
U.S. State Department spokesperson Mark Toner said the killing of the boy, identified in reports as 12-year-old Abdullah Issa, was “appalling” and the government was trying to get more information about the horrific footage of the child’s death.
The group accused of being responsible for the beheading, the Nour al-Din al-Zinki Movement, was reportedly one of the groups the U.S. government supported and provided weapons to in the fight against the regime of President Bashar al-Assad.
In his remarks Tuesday, Toner said a confirmation of the details about the beheading would “give us pause about any assistance or, frankly, any further involvement with this group.”
According to Storyful, which monitors and verifies photos and videos shared on social media, numerous social media accounts claimed the Islamist rebel group Jaish al-Fatah (the Army of Conquest) or its affiliate the Nour al-Din al-Zinki Movement captured the boy and accused him of fighting with a government-aligned Palestinian group, the Liwa al-Quds (Jerusalem Brigades).
Liwa al-Quds refuted the claims Issa was a fighter and, according to the BBC, said he was just a child from a refugee family living in the poor Handarat camp near Aleppo.
The group accused the Nour al-Din al-Zinki movement of enacting “cheap and despicable revenge” after suffering losses on the front lines of the conflict.
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Liwa al-Quds claimed the boy was also in poor health — he is seen with a video taken before the beheading with an intravenous tube in his arm.
For its part, the Nour al-Din al-Zinki Movement is trying to distance itself from the killer and the other men who appear in the video, and claimed it was taking action against “individual errors that represent neither our typical practices nor our general policies.”
Amnesty International said the video is the latest “abhorrent signal” that opposition groups are carrying out serious abuses with impunity.
“This horrific video showing the beheading of a boy suggests some members of armed groups have truly plumbed the depths of depravity. It is yet another gruesome example of the summary killing of captives, which amounts to a war crime,” said Philip Luther, Director of Amnesty International’s Middle East and North Africa Program.
With files from Global News and The Associated Press