JERUSALEM (CNN)  -- The international group Human Rights Watch is accusing Israel of firing weapons containing white phosphorus into Gaza. The group demands that the alleged practice cease. Israel is declining to say whether bursts like this over Gaza involve white phosphorus. The group's  researchers in Israel "observed multiple air-bursts of artillery-fired white phosphorus over what appeared to be the Gaza City/Jabaliya area" on Friday and Saturday, the organization said on its Web site. "Israel appeared to be using white phosphorus as an 'obscurant' [a chemical used to hide military operations], a permissible use in principle" under the laws of war, the HRW posting said.
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Researchers in Israel saw bursts of white phosphorus over Gaza, group says
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White phosphorus can burn people, set structures on fire
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Protocol allows use when "not specifically designed to cause burn injury to persons"
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Group: Use in densely populated Gaza would violate international humanitarian law
@placeholder does not specify the types of munitions or the types of operations it is conducting."