Jerusalem ( CNN ) -- Two of nine mortars fired from Gaza into Israel on Wednesday contained white phosphorous , Israeli police told CNN . Bomb disposal experts examined the mortars and confirmed that two contained white phosphorous , a police spokesman said . It was not the first time that Hamas has attempted to target Israel using mortars containing white phosphorous , the spokesman said . White phosphorus ignites and burns , creating white smoke when it is exposed to oxygen . Militaries use it as a smoke screen to protect troops during combat . If it comes in contact with skin , however , white phosphorus creates an intense and persistent burn . Israel itself has been roundly criticized for firing white phosphorus shells over densely populated areas during the Gaza offensive that began in late 2008 . However , in a July report to the United Nations , Israel pledged to limit the use of munitions containing white phosphorus and to make greater efforts to protect civilians during conflicts . The latest allegations and violence come amid a fresh round of Middle East peace talks that began Tuesday in Egypt and continued Wednesday in Jerusalem .
Bomb experts examined the mortars . White phosphorous can create an intense and persistent burn . The mortar was found to have a hole in it, which is consistent with being hit by shrapnel or small arms fire from insurgents firing at them.