The "rebels" alleged that the boy was a fighter for a Palestinian group on the Syrian government side. But the boy looks very small and weak, has infusion tubes in his arm and no military attributes like a uniform or weapons.

There is now additional information about the case:

8:08 AM - 20 Jul 2016 Elijah J. Magnier @EjmAlrai
#Palestinian child, Abdullah Issa, was at Hospital, beheaded by Mateen al-Nahlawee coz his father is a militant.

#Palestinian Abdullah Issa was suffering from lack of oxygen n the bloodstream causes thalassemias and needed blood transfusion every month+

He was not fighting among Al-Quds pro-gov group but his father. He was a patient at the Hospital in #Aleppo when beheaded by pro-#US Zinki.