The mysterious death of a 30-year-old Palestinian gas station attendant in Israeli custody stoked new West Bank clashes Sunday, along with Israeli fears of a third Palestinian uprising.

A senior Palestinian official alleged that Arafat Jaradat was tortured by Israel's Shin Bet security service, citing an autopsy he said revealed bruising and two broken ribs.

Israel's Health Ministry said the autopsy did not conclusively determine the cause of death, but that the bruising and broken ribs were likely the result of attempts to revive the detainee.

Jaradat's death came at a time of rising West Bank tensions, including several days of Palestinian marches in support of four hunger-striking prisoners in Israeli lockups. In all, Israel holds nearly 4,600 Palestinians, including dozens who have never been formally charged.

Frozen Israeli-Palestinian peace talks, the recent re-election of Israeli hard-line Prime Minister Benjamin Netanyahu, a Palestinian cash crisis and the Palestinians' sense of being abandoned by the Arab world seem to have created fertile ground for a third Palestinian revolt.

Over the weekend, Israel's army chief convened senior commanders to discuss the growing unrest.

Jaradat's death "is liable to become the opening shot" in a third uprising, Israeli military commentator Alex Fishman wrote in the Yediot Ahronot daily Sunday, arguing that the "Palestinian street has been boiling with anger for a number of weeks now."

However, Israeli officials have previously expressed concern about a new uprising, only to see bursts of Palestinian protests fizzle.

The first uprising, marked by stone-throwing protests and commercial strikes, erupted in the late 1980s and led to Israeli-Palestinian negotiations. The second uprising broke out in 2000, after failed talks on a final peace deal, and it was far deadlier, with Israel reoccupying the West Bank after bombings and shootings.

In recent years, the West Bank has been relatively calm. Despite recent tensions, the Palestinian self-rule government has not broken off security coordination with Israel in their joint campaign against Islamic militants.

Palestinian activists also say they learned from the mistakes of the armed revolt a decade ago and are turning to more creative protests against Israel's 45-year rule over lands they want for a future state.

Former Palestinian security chief Jibril Rajoub, speaking in Hebrew on Israel Radio, tried to reassure Israelis, declaring Sunday "on behalf of the entire Palestinian leadership that there is no plan to lead to bloodshed."

Jaradat, a father of two from the West Bank village of Saeer, died in Megiddo Prison in northern Israel on Saturday, six days after his arrest on suspicion of stone throwing.

Jaradat's attorney, Kamil Sabbagh, said his client told an Israeli military judge Thursday during a hearing that he was being forced to sit for long periods during interrogation. The detainee also complained of back pain and seemed terrified to return to the Shin Bet lockup, although he did not have any apparent signs of physical abuse, Sabbagh said.

After the court hearing, the judge ordered Jaradat to be examined by a prison doctor.

The Shin Bet said that during interrogation, Jaradat was examined several times by a doctor who detected no health problems. On Saturday, he was in his cell and felt unwell after lunch, the agency said.

"Rescue services and a doctor were alerted and treated him," the statement said. But "they didn't succeed in saving his life."

On Sunday, Israel's forensics institute performed an autopsy attended by a physician from the Palestinian Authority.

After being briefed by the Palestinian physician, Issa Karake, the Palestinian minister of prisoner affairs, told a news conference late Sunday that Jaradat had suffered two broken ribs on the right side of his chest. The autopsy also showed bruises on Jaradat's back and chest.

Israeli officials initially said Jaradat apparently died of a heart attack, but Karake said the Palestinian physician told him there was no evidence of that.

Jaradat "faced harsh torture, leading to his immediate, direct death. Israel is fully responsible for his killing," Karake said.

Israel's Health Ministry said Jaradat did not suffer from disease and that it was not possible yet to determine his cause of death conclusively.

The Israeli human rights group B'Tselem said the Shin Bet routinely holds detainees in isolation for extended periods during interrogation, keeping them in cells where the lights are never turned off.

Citing prisoner affidavits, B'Tselem spokeswoman Sarit Michaeli said physical mistreatment has dropped sharply in recent years but has not disappeared.

Detainees have filed some 700 complaints about mistreatment by Shin Bet agents in the past decade, but none has led to a criminal investigation, she said.

In the West Bank, meanwhile, Palestinians protesting Jaradat's death threw stones at Israeli troops in several locations Sunday, including the city of Hebron and at a checkpoint near the military's Ofer prison.

In the clash near the checkpoint, troops fired live rounds, shooting the 15-year-old son of the commander of the Palestinian Preventive Security Service in the chest and stomach, said Palestinian health official Dr. Ahmed Bitawi. The teen, Walid Hab al-Reeh, was in stable condition, while another man was wounded in the arm, Bitawi said.

The Preventive Security Service is key to security coordination with Israel. The Israeli military said it was aware of a report that a Palestinian youth was seriously hurt by gunfire, but could not confirm that soldiers used live rounds to disperse the protest.

Kadoura Fares, who heads a Palestinian group advocating for prisoners, urged Palestinians on Sunday to keep demonstrating. He also said that one of the four hunger-striking prisoners, Jafar Izzeldeen, was moved to a hospital Sunday because his condition was deteriorating.

Recent West Bank protests have focused on the fate of prisoners, an emotional Palestinian consensus issue.

Tens of thousands of Palestinians have been imprisoned since Israel captured the West Bank, Gaza and east Jerusalem in 1967, meaning virtually every Palestinian family has had someone locked up.

The detainees are held on a range of charges, from stone-throwing to deadly attacks. Most Palestinians embrace them as heroes resisting occupation, while Israelis tend to view them as terrorists.