White phosphorus, also known as WP, is classified as an incendiary weapon. The Geneva Convention on the use of conventional weapons defines "incendiary weapons" as “primarily designed to set fire to objects or to cause burn injury to persons through the action of flame, heat, or combination thereof, produced by a chemical reaction of a substance delivered on the target.”

Use of white phosphorus in areas with “concentration of civilians” is illegal under international law.

In medical terms, white phosphorus can be exposed to soft tissue in the human body when inhaled or ingested. Deep absorption of the chemical can cause heart, liver and kidney damage and, in some cases, death. Its impact on skin resembles burn injuries that have a yellowish color and a pungent odor.

USE IN GAZA

Amnesty International and Human Rights Watch have both documented Israelzzz*zs use of white phosphorus in its Dec. 2008 - Jan. 2009 offensive on Gaza.

Human Rights Watch published an in-depth report on March 25, 2009, titled “Rain of Fire: Israel’s unlawful use of white phosphorus in Gaza.” It concluded:

“The Israel Defense Forces (IDF) repeatedly exploded white phosphorus munitions in the air over populated areas, killing and injuring civilians, and damaging civilian structures, including a school, a market, a humanitarian aid warehouse and a hospital.”

The 75-page document produced first hand evidence of Israeli military’s illegal use of white phosphorus in densely populated areas during the Gaza war. One of the prominent instances was the firing of phosphorus shells by Israeli forces on January 15, 2009, around an UNRWA compound in Gaza that was sheltering civilians. This account includes statements from UNRWA officials of repeated requests to the military to stop the attacks, which continued for two hours. The report concluded that such usage was “deliberate,” “reckless” and “indiscriminate."

Amnesty International called for an immediate arms embargo on Israel by the US, which continues to supply Israel with weapons.

After denying the use of white phosphorus in Gaza, Israeli officials admitted its use on April 23, 2009 saying they had ordered a halt to its deployment on Jan. 7, 2009.

INTERNATIONAL LAW

Article two, protocol III of the 1980 UN Convention on Certain Conventional Weapons states: "It is prohibited in all circumstances to make the civilian population as such, individual civilians or civilian objects, the object of attack by incendiary weapons."

However, the convention allows use of weapons containing white phosphorus for military purposes that do not use its toxic properties as a chemical weapon.

PRECEDENT

The use of white phosphorus in war is a new phenomenon. US army generals have described its impact as comparable to napalm, which was used by US forces in the Vietnam War.

Israelzzz*zs use of white phosphorus in Gaza has no precedent in international law. The closest case of similar use was in the Iraq war of 2003, where allegations arose over the use of "unusual" weapons by US coalition troops, specifically in Fallujah.