The stunt saw children lie on the ground while a man dressed as a soldier walked around them pointing a Kalashnikov at them.
The act symbolised the death of Palestinian children at the hands of the Israeli military during the recent armed intervention and was carried out during a Pro-Gaza march in Paris on Saturday.
Authorities were concerned bythe images and launched an immediate probe to find out whether the rifle was real or fake.
On Sunday France Info radio revealed that the weapon was indeed fake after speaking to the man, who was dressed as the soldier.
The protester, named Mohamed, said the rifle was a toy gun and the act was set up “to show what is really happening in Palestine”.
The latest pro-Palestinian march in the French capital saw up to 8,000 protesters take to the streets to condemn Israel’s bombardment of Gaza.
It is the latest in a series of similar rallies that have taken place in the capital, some of which have ended in violence.