A human rights groups said Saturday Israel is using white phosphorus in violation of international law. Human Rights Watch (HRW) said that given Gaza's high population density, and the chance that civilians would be hurt, Israel should discontinue the use of the substance. "We completely believe that the use of white phosphorus in densely populated areas is a violation of international humanitarian law," Marc Garlasco, a military analyst with the group, told Deutsche Presse-Agentur dpa by phone from the Israel-Gaza border. "White phosphorus has a significant, incidental, incendiary effect that can severely burn people and set structures, fields and other civilian objects in the vicinity on fire," HRW explained in a statement. "White phosphorous can burn down houses and cause horrific burns when it touches the skin," Garlasco said. "today we saw them use it over the Jabalia refugee camp, a densely populated area," Garlasco said. He said the military was "not taking proper precautions to protect the civilian population."