On Sunday Human Rights Watch said that Israel's military are using the incendiary agent white phosphorus in their fired artillery shells.
The use of the chemical was suspected when a doctor saw 10 burn victims with skin peeling off their faces and bodies. Doctors however didn't have the expertise to say for certain that phosphorous was actually used.
Researchers in Israel from the rights group witnessed hours of artillery bombardments that sent trails of burning smoke indicating white phosphorus over the Jebaliya refugee camp in northern Gaza. But they could not confirm injuries on the ground because they have been barred from entering the territory.
Phosphorous can cause undue pain and burns if it touches the skin. It can also set fires when it touches the ground.
Human rights groups have in a written statement called out to Israel not to use it in Gaza's crowded areas.
Israel has denied commenting whether they are using the substance or not, they simply commented that they are within the bounds of international law.