From Human Rights Watch - A review (http://www.hrw.org/en/node/10911/section/3)

Palestinian Rocket Attacks

From September 2005 through May 2007, Palestinian armed groups fired almost 2,700 rockets into Israel, killing 4 Israeli civilians, and injuring 75 civilians and at least 9 soldiers, according to the United Nations Office for the Coordination of Humanitarian Affairs (UNOCHA) (see Appendices III-V for casualty and weapons numbers). Two of those deaths occurred in the last two weeks of May 2007. An additional six civilians died in rocket attacks from mid-2004 through August 2005. Palestinian rockets have also killed at least two and injured at least 21 Palestinian civilians when they landed short of the Israeli border. The rockets, made in Gaza and generically known as "Qassams" after the name of the armed wing of Hamas, the Islamic Resistance Movement, are highly inaccurate and cannot be directed at a specific target.

Communities in the western Negev in Israel, in particular the city of Sderot, have suffered from these attacks. The 10 Israeli civilians killed by Palestinian rocket attacks since mid-2004 range from 2 to 57 in age and include four children. The attacks also have inflicted property damage and created a pervasive climate of fear in affected Israeli communities. Eshel Margalit of Moshav Nativ Ha'asara, for example, told Human Rights Watch how his daughter narrowly escaped becoming a victim of a rocket attack. Margalit said when a siren went off warning of an incoming rocket, his daughter was upstairs in the family study working on the computer: "I yelled to her but she was not eager to leave the computer, she was 18, you know," Margalit said. "She came down and we were running to the secure room when the Qassam hit the house." The rocket penetrated the roof and exploded in the study. "We went up, opened the door, and saw the room was destroyed. When my daughter realized what could have happened she burst into tears The Qassams have changed our lives. There is a lot more stress and anxiety."[2]

Hamas, Islamic Jihad, al-Aqsa Brigades, and the Popular Resistance Committees have all claimed responsibility for firing rockets into Israel, though Hamas largely complied with self-imposed halts to such attacks between February and June 2006 and between November 2006 and late April 2007. These groups have justified their attacks as actions of self-defense and reprisals for Israel's actions against the Palestinians. A typical statement after a strike declares that it is a response "to the crimes of occupation against our children, women, and elderly."[3]

The Palestinian rocket attacks violate international humanitarian law, also known as the laws of war, which governs the conduct of the parties during armed conflict. Where an attack on a military target is intended and that target is in or near a civilian area, the Palestinian rocket attacks are indiscriminate because they cannot distinguish between military targets and civilians. Where there is no intended military target and the rockets are launched into a civilian area, they constitute deliberate attacks against civilians. Given that the rocket attacks have inflicted very little damage on Israeli military assets, their primary purpose seems to be to kill civilians or at least to spread terror among the Israeli civilian population, both of which IHL prohibits.

Even assuming the rocket attacks were intended as reprisal for Israeli attacks that kill and injure civilians, as Palestinian groups often claimed, they still are unlawful under international humanitarian law. The law governing reprisals-defined as otherwise unlawful actions that are considered lawful when used as an enforcement measure in reaction to an adversary's unlawful acts[4]-does not permit direct or indiscriminate attacks on civilians, in part for reasons that these rocket-artillery exchanges demonstrate: even attacks ostensibly launched as reprisals often spur counterattacks by the other side, yielding an endless cycle of civilian injury and death. As the leading treaty in this area provides, one side's targeting of civilians or civilian objects can never justify like targeting by the other side.[5]

Palestinian armed groups also at times endanger civilians by placing their rocket launchers near residential areas in Gaza. The IDF claims that over the course of 2006 Palestinian armed groups moved their launchers increasingly close to residential areas, presumably because return IDF artillery fire had made open fields a less attractive military option. Human Rights Watch's interviews provide evidence that in at least one locale Palestinian groups fired or tried to launch rockets from within 100 meters of populated apartment buildings. While Gaza is densely populated, and open areas are relatively scarce, combatants still have an obligation to take all feasible precautions to protect civilians and this includes avoiding placing launchers within or firing from close proximity to populated areas.