Several Palestinians have been reported killed in protests in Jerusalem over restrictions at Haram al-Sharif, also known as Temple Mount. Palestinian President Abbas meanwhile froze relations with Israel.
The Palestinian protests - triggered by tensions over the placement of metal detectors and turnstiles at a Jerusalem holy site - turned into clashes in which two men were shot dead on Friday.
News of a third death came from the Palestinian health ministry later. The ministry also said at least 400 people had been hospitalized. Rubber bullets and tear gas were used by Israeli police, although the shooting fatalities were caused by live rounds.
Security forces have prohibited Palestinian men under the age of 50 from entering Jerusalem's Old City for Friday Muslim prayers this week, but have allowed access to women of all ages.
Typically, thousands of worshippers descend on Fridays to the Haram al-Sharif mosque compound, known to Jews as the Temple Mount and site of the Al-Aqsa mosque. Muslim leaders meanwhile urged worshipers to skip Friday prayers at neighborhood mosques across the city and instead go to the shrine to boost crowd numbers, which were expected to rise to the tens of thousands.
Palestinians have also been urged to converge on Israeli military checkpoints in the occupied West Bank.
Abbas cuts ties with Israel
Palestinian President Mahmoud Abbas meanwhile announced that he was going to suspend all contacts with Israel because of the controversial new security measures. It was not immediately clear, however, if this meant that Palestinians were also stopping their long-standing security coordination with Israel.
DW's Israel correspondent Tania Kramer, who is in Jerusalem, said there were reports of riots and sporadic outbursts of violence in various parts of the city by early afternoon. Police had a heavy security presence, erecting check points and turning away Palestinians heading into Jerusalem.
"It's a bit of an unclear and volatile situation," Kramer said.
"Most people were not even able to get close to the old city, they were stopped by security in the street."
"Any change to this very sensitive holy site usually sparks very strong reactions. So far Israel has not backed down to remove those metal detectors. There might be a reassessment, I think it depends on what happens in the next few hours and also after the evening prayers because it is so volatile."
The restrictions meant that less than a thousand worshippers gathered outside the the holy site for Friday prayers, fewer people than at other evening prayers over the past week.
Worshippers have been holding prayers on the streets outside the Haram al-Sharif mosque compound since last Sunday when Israeli police installed metal detectors and turnstiles at its entrance.
The new security measure proved instantly controversial. "Clerics have called on Palestinian worshipers not to use those electronic doors because, for a Palestinian this is a very sensitive holy site and everything that Israel tries to do there is seen as changing a very fragile status quo," Kramer told DW.
There have also been clashes between Palestinian protesters and Israeli police, including on Thursday when more than 20 protesters were injured in Jerusalem.
Israeli authorities say the security measures are necessary after three Arab Israeli gunmen killed two police officers at the entrance of the shrine. The attackers were shot dead.
The standoff over the holy site has raised concern it could unleash a third Palestinian intifada, or uprising. The second intifada was triggered in 2000 after former Israeli President Ariel Sharon visited the holy compound.
There was reportedly debate within the Israeli security establishment over the necessity of the metal detectors, with the military and the Shin Bet security service finding them unnecessary.
But after a security meeting on Thursday Prime Minister Benjamin Netanyahu decided not to remove the metal detectors and gave police authority to make the decision.
Gilad Erdan, Israel's public security minister, argued the detectors were needed to maintain security. "The Israeli police needs these metal detectors so the security checks can give a proper response to the security considerations," he said on Thursday.
The issue has quickly taken on an international dimension as the Haram al-Sharif mosque compound is considered the third most holy site in Islam after Medina and Mecca.
Israel and Jordan have been in talks to defuse tensions.
The White House issued a statement on Wednesday urging Israel and Jordan to find a solution that maintains security and "the status quo."
Palestinians accuse Israel of attempting to alter the status quo in which Jews are forbidden to worship there and the holy site is under the custodianship of Jordan and managed by the Islamic Waqf religious trust.
Palestinian President Mahmoud Abbas also urged the United States to intervene with Israel to drop the new security measures. In a call with White House senior advisor Jared Kushner on Thursday, he warned that the situation could spiral out of control, Palestinian news agency WAFA reported Friday
Located in annexed East Jerusalem, the holy site has been under Israeli control since the 1967 war.
Jews consider the Temple Mount to be the holiest site in Judaism.
rc/rt (Reuters, AP, AFP, dpa)