"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."

Amnesty urges the Palestinian Authority to arrest and bring to justice those who order, plan or carry out such attacks.

Over the years the bulk of Amnesty's work in the region has highlighted abuses by Israel, making Thursday's report an unusual departure.

"I am really happy that Amnesty officials have seen the light," said Israeli Justice Minister Meir Sheetrit.

This is Amnesty International's seventh report on the human rights situation in the region since the Palestinian uprising against Israeli rule erupted in September 2000.

It says the attacks by Palestinian militants on civilians violated "fundamental principles of humanity which are reflected in international humanitarian law".

Usually it is Israel that Amnesty criticises

The group says that since the Palestinian uprising began in September 2000 at least 350 civilians - the vast majority of them Israeli - have been killed in more than 128 attacks by Palestinian militants.

More than 1,500 Palestinians have been killed in the violence.

Recent opinion polls conducted in Palestinian areas suggest there is strong support for suicide bombings, which people see as part of the struggle to liberate their land.

"Whatever the cause for which people are fighting, there can never be a justification... under international law... for direct attacks on civilians," Amnesty said.