A bearded Islamist who lived on liquids and minerals for 66 days to protest his open-ended incarceration in Israel, winning his freedom, has inspired more than 1,000 other Palestinian prisoners to follow him, putting pressure on Israel.
The prisoners who have joined the strike in recent weeks are demanding better conditions and an end to imprisonment without charges.
The mass action could leave Israel with tough choices. It does not want to be seen as caving in to prisoners, many of whom were involved in deadly attacks _ but it might face a harsh, even violent reaction if any of them die.
Some say the strike also is an expression of the frustration that many Palestinians feel as they exhaust options to pressure Israel.
"Hunger-striking was the only thing I could have done," said Khader Adnan, who was released by Israel last month after his 66-day hunger strike. "It was the only power I had: disobedience."
The militant groups Islamic Jihad and Hamas, which have killed hundreds of Israelis in suicide bombings and other attacks over the years, have spearheaded the current hunger strike.
Their embrace of a tactic made famous by the legendary Indian leader Mohandas Gandhi underscores how Palestinians have reduced their use of violence since a bloody uprising against Israel a decade ago. The groups still use violence to further their goals, but say they are inspired by the success of mass protests during the Arab Spring uprisings.
Israel says the militants may have changed their tactics but have not abandoned their goal of eliminating the Jewish state.
According to prison officials, at least 1,600 of the 4,600 Palestinians held by Israel are refusing food. Palestinians say about 2,500 strikers are striking.
Most of the protesters joined the strike on April 17. Two others, Bilal Diab and Thaer Halahleh, have been striking for 70 days.
Diab is shackled to a civilian hospital bed, according to Hadas Ziv of Physicians for Human Rights Israel. Halahleh is under medical supervision in a prison clinic with nine other hunger strikers, and most have refused food for more than 50 days, according to Israel's prison service.
Some are taking liquids and mineral supplements, while others are refusing even that, said prison spokeswoman Sivan Weizman.
Ziv said hunger strikers generally faced grave dangers after 40 days.
If any of them die, it could unleash a broader backlash. Both Hamas and Islamic Jihad leaders have warned of retaliation. It could also encourage Palestinians to take to the streets.
The strikers include militants serving multiple life sentences for participating in deadly attacks against Israeli civilians.
Also among them are men detained without charge for indefinite periods of time, a system called "administrative detention," including Diab and Halahleh.
Adnan, an Islamic Jihad member who urged Palestinians to kill Israeli civilians, was also held under administrative detention before he was freed in exchange for ending his hunger strike.
Israeli officials say administrative detention is used when a person is considered an immediate threat to security, and where airing evidence would endanger intelligence-gathering networks. About 300 Palestinians are in administrative detention.
The prisoners' main demand is an end to the practice, halt solitary confinement and allow families from the Hamas-ruled Gaza Strip to visit. Israel stopped the family visits after Hamas captured an Israeli soldier in 2006. The soldier came home in a prisoner swap last October, and Palestinians say the punitive practice should end.
The current hunger strike has aroused empathy among Palestinians, where most families knows someone who has spent time in an Israeli jail. Even so, demonstrations supporting them have been small.
In the northern West Bank town of Kufr Rai, Diab's hometown, some 150 high school girls chanted in support of the striker recently, holding his picture and waving a Palestinian flag. Nearby, residents flitted in and out of a solidarity tent decked with pictures of the hunger strikers.
"If I could speak to my son, I would say: 'May your morale be high, may God be pleased with you. We are worried about you. Your blood isn't cheap, you are worth more than all the world," said Diab's mother, Missadeh.
Israeli officials say that giving in to prisoners' demands would embolden them. They cite the deal struck with Adnan, saying it only encouraged hundreds more to refuse food.
"We can't have a situation where every terrorist who goes on a hunger strike gets a 'get out of jail free' card," said Israeli spokesman Mark Regev.
A committee has been appointed to look into the demands, said prison spokeswoman Weizman.
On Monday, Israel's Supreme Court rejected an appeal by Diab and Halahleh to declare an end date to their open-ended detention, but the court urged security services to investigate further before extending their terms again.
Israel has held Diab since last August, according to the Palestinian prisoner rights' group Addameer. Halahleh has been held without charge since mid-2010, and previously spent more than six years in administrative detention. Both belong to Islamic Jihad.
Diab's brother, Issam, said his brother's 70-day fast has been worth it.
"If he dies, that would be tragic," he said. "But this is freedom, and there is a heavy price for freedom."
Hadid reported from Jerusalem. Additional reporting by Mohammed Ballas in Kufr Rai, West Bank, and Ibrahim Barzak in Gaza City, Gaza Strip. Follow Hadid on twitter.com/diaahadid