TEL AVIV - Six Palestinian prisoners on a hunger strike in Israeli prisons are in danger of "imminent death," a result that could trigger an outbreak of violence in the relatively peaceful occupied West Bank, according to Israeli and Palestinian officials and activists.

The six are part of a larger group that some activists estimate is now in the thousands after some 1,600 Palestinians joined a smaller hunger strike on April 17. More joined in solidarity after that. They are protesting a lack of rights in Israeli prisons, as well as "administrative detention" which allows Israel to indefinitely renew six-month prison terms with no charges.

Today was the 74th day of hunger striking for administrative detainees Bilal Diab and Thaer Halahla, currently in a prison clinic despite pleas from the Red Cross and Israel's Physicians for Human Rights to transfer them to hospitals. The four other prisoners have been striking for over 40 days.

The six "are in imminent danger of dying," the Red Cross said in a statement this week. "We urge the detaining authorities to transfer all six detainees without delay to a suitable hospital so that their condition can be continuously monitored and so that they can receive specialized medical and nursing care."

An Israeli Prison Service spokeswoman told the Palestinian Ma'an news service today that the men would be transferred to a hospital "if it is necessary," but that "as of now, I know that those who should be receiving extra care are receiving it."

"We need immediate intervention now" from the international community, activist Raya Ziada told ABC News. Her brother is in an Israeli prison serving a 30 year sentence. If prisoners die, she said, "I think there will be an explosion of frustration for not intervening."

Top Palestinian officials have warned of an outbreak of violence in the West Bank with President Mahmoud Abbas saying "it is very dangerous."

"If anybody dies today or tomorrow or after a week it would be a disaster and no one could control the situation," he told Reuters earlier this week.

In addition to administrative detention, the protest centers around solitary confinement, family visitation rights and access to books and education. Many of the 4,700 Palestinian prisoners are from the Hamas-controlled Gaza Strip and their families are barred from visiting. These punishments came into effect while Israeli soldier Gilad Shalit was held in Gaza by Hamas for five years. He was released in October.

"The atmosphere is really tense and the level of tension and solidarity [with the prisoners] is growing on a public level," said Ghassan Khatib, a spokesman for the Palestinian Authority. "Those prisoners are not asking to be released. They asking for basic rights according to international law."

He said so far there were no indications that Israel was bowing to the pressure. "I don't know what will happen," Khatib said.

Those in administrative detention are asking to be charged or released, a demand echoed by United Nations Secretary General Ban Ki-Moon on Wednesday. Just over 300 Palestinians are in administrative detention, which Israel says is essential to protect the identities of Palestinian informants whose names would otherwise be revealed in court.

Earlier this year, two administrative detainees were released by Israel following prolonged hunger strikes. Khader Adnan's 66-day strike ended in Feburary when Israeli authorities agreed not to extend his detention. He was was released in April. Hana Shalabi was also released into Gaza last month after a hunger strike that lasted more than 40 days.

Both Adnan and Shalabi, as well as Diab and Halahla, are accused of belonging to the militant group Islamic Jiahd. The group has warned that it will end a current ceasefire with Israel if a prisoner dies.

A spokesman for Israeli Prime Minister Benjamin Netanyahu wouldn't discuss ongoing negotiations, but said they want to see an end to the hunger strikes as soon as possible to avoid the possibility of "riots all over the West Bank." They also have to avoid "the situation they get a get out of  jail free card."

"If one of these hunger strikers commits suicide, you could have an instigation of violence which no one wants to see," Netanyahu's spokesman Mark Regev told ABC News. "The concern is that Islamic Jihad and Hamas have an interest in violence."