(Reuters) - A hunger strike by Palestinian prisoners against Israel´s jail policies has swollen in weeks from a protest by a handful to a national movement with around 1,400 participants.

Several are at risk of dying, including Bilal Diab and Thaer Halahlah, both on their 64th day without food, their Palestinian lawyer said. Eight other detainees have been hospitalized.

But most joined the fast two weeks ago, demanding an end to Israel´s imprisonment without trial for individuals the state deems a security threat, restrictive visiting rights and limited access to educational materials.

Palestinian President Mahmoud Abbas said on Monday his government would refer the issue of prisoners to the United Nations, internationalizing a campaign in which all the often divided and acrimonious Palestinian factions are taking part.

"In prison, hunger is the only weapon ... my brother is defending not just his own rights and honor, but those of the whole Palestinian people," said Bassam Diab, a former detainee and brother of jailed hunger strikers Bilal and Azzam Diab.

Israeli prisons commissioner Aharon Franco has named a panel to address the hunger strikers´ demands, and on Monday told Marwan Barghouti, a Palestinian leader once convicted by Israel of murder, Palestinian officials said.

"The director of prisons communicated that the prison administration would study seriously their demands and will respond to them after a short time," said Qaddoura Fares, chairman of the main Palestinian prisoners´s organization.

Sivan Weizman, a spokeswoman for the Israeli Prisons Authority, said the Israeli panel was set up before the hunger strike was launched but confirmed Franco had told prisoners he would review the committee´s recommendations.

Israeli authorities say some 1,450 prisoners are on hunger strike. Palestinian sources give varying figures, all well over 1,000.

There are more than 4,000 Palestinian prisoners in Israeli jails, of whom around 320 are held in "administrative detention", or jailed without trial, a security measure Israel defends as a precaution to protect undercover sources.

Many however have been convicted in open proceedings of killing Israeli civilians or plotting attacks.

"STONES, GUNS, HUNGER"

At the forefront of the new wave of hunger strikes are members of Islamic Jihad, proscribed by Israel and other governments as a terrorist organization.

"God holds the decision: sometimes we are called to resist with stones, sometimes with guns, and other times through hunger and perseverance," Khader Adnan, a leader of Islamic Jihad and survivor of a 66-day jail fast, told Reuters from a Jenin refugee camp.

"I didn´t realize my actions would lead to of this scale. But naturally people saw what I accomplished and took notice," he said.

After his hunger strike against his "administrative detention", Israel commuted Adnan´s sentence and released him two weeks ago.

Fellow Islamic Jihad members followed his example, and further Israeli concessions helped inspire the current movement.

His campaign has prompted solidarity marches throughout Gaza and the West Bank, and widespread graffiti of Adnan´s bearded visage and proclamations like "Hungry 4 freedom" even in the well-to-do neighborhoods of Ramallah.

"In prison, there are no factions, we´re just flesh. God willing this will lead to a unified, national movement," Bassam Diab, like his brother an Islamic Jihad member, said from the family´s modest home in the northern village of Kufr Ra´i.

Prisoners especially resent Israel´s "Shalit law," restricting prisoners´ access to families and to educational materials as punishment for the harsh, five-year captivity of Israeli soldier Gilad Shalit by Hamas militants.

The law remains in force despite a prisoner swap deal which saw hundreds of Palestinian detainees released in October in exchange for the soldier´s freedom.

"Dialogue with them is not possible, there´s no alternative," said Qahira Saadi, a mother of four sentenced to life in prison by Israel in 2002 for her alleged role in a suicide bombing, but released in exchange for Shalit.

"This is a battle, and hopefully it will come to a good end," she said.(Additional reporting by Nidal al-Mughrabi in Gaza; editing by Andrew Roche) (© Thomson Reuters 2012. 04/30/12)