Amnesty International condemned Palestinian homicide bombings and other attacks on Israeli civilians Thursday as "crimes against humanity" and unjustified by Palestinian political grievances.

The London-based human rights organization had previously accused Israel of violating Palestinian rights in the Mideast conflict, but the lengthy report focused on the Palestinian violence that amnesty said had killed about 350 Israeli civilians.

"The attacks against civilians by Palestinian armed groups are widespread, systematic and in pursuit of an explicit policy to attack civilians," the Amnesty report said. "They constitute crimes against humanity ... They may also constitute war crimes."

Palestinian officials dismissed the report as biased and unbalanced.

Palestinian Cabinet secretary Ahmed Abdul Rahman said the Palestinian leadership and prominent Palestinian moderates had condemned homicide bombings. But he added, "all that is happening to Israeli citizens is a normal consequence for their occupation and rejection of Palestinian rights."

Ismail Abu Shanab, spokesman for the militant Islamic group Hamas, which has carried out the largest number of homicide bombings, dismissed the report as "completely biased."

"It reflects the same American policy that gave the legitimacy to the (Israeli) occupation of West Bank cities and to the daily actions committed by the Israeli army against the Palestinians," he said.

Hamas says it will continue to carry out bombings despite the calls to stop by the Palestinian Authority.

Some Palestinian extremists argue that since most Israelis, both men and women, serve in the military, virtually all Israelis are legitimate targets for attack. Also, many Palestinians claim that Israeli settlers, including women and children, are valid targets because they live in the overwhelmingly Palestinian areas of the West Bank and the Gaza Strip.

Many bomb attacks have also hit buses or cafes where a small number of uniformed soldiers may be present among a larger group of civilians.

Amnesty said such attacks were unjustified.

"The occasional presence of soldiers among passengers on ordinary commuter buses ... in a cafe or shoppers in a market does not make such venues legitimate targets for attacks," the Amnesty report added.

Many Palestinians see the attacks as a part of their struggle against Israel's occupation of the West Bank and Gaza and as part of an effort to achieve a future state. They also see the attacks as retaliation against the killings of Palestinian including children by Israel security forces.

Israel says that its military actions are in response to Palestinian violence, and that its operations target those responsible for attacks.

The Amnesty report said "no violations by the Israeli government, no matter their scale or gravity, justify the killing of ... civilians."

Opinion polls have consistently shown that homicide bombings have strong support among the Palestinian population. One recent poll showed 68 percent of Palestinians approved of the attacks, down from about 74 percent at the end of last year. In Palestinian public rallies, homicide bombers are glorified as martyrs, with posters of the bombers plastered on walls throughout Palestinian cities and towns.

The Amnesty report noted that some Palestinians believe targeting civilians is wrong, though their voices are not as loud as those who favor the attacks. Amnesty International called on the Palestinian Authority to ensure that those who order, organize or assist such attacks are brought to justice.

Hundreds of civilians have been killed on both sides of the conflict, though Israel argues that its security forces do not intentionally target civilians, while Palestinian bombers attempt to maximize civilian deaths.

According to the Amnesty report, about 350 Israeli civilians have been killed in 130 attacks by Palestinian militias since the beginning of the fighting in September 2000.

According to overall figures compiled by The Associated Press, 1,752 people have been killed on the Palestinian side and 565 on the Israeli side. The totals include 71 Palestinian suicide bombings that have killed 250 Israelis.