JERUSALEM – Crowds of Palestinian youths rampaged in east Jerusalem Wednesday following the shooting death of a local man, clouding fragile peace efforts even as the Palestinian president signaled he may back away from threats to quit negotiations if Israel resumes West Bank settlement construction.

The “moratorium” on construction was declared last November under intense U.S. pressure to help coax the Palestinians into talks with the government of Prime Minister Benjamin Netanyahu, who — despite having accepted the principle of a Palestinian state — inspires very little faith in the Palestinians. Netanyahu said all along that the measure would end on Sunday, and the Palestinians have threatened to walk away from the talks if this occurs.

The impasse and looming deadline have created a palpable tension that has built throughout the week.

A glimmer of hope arrived from the United States, where Palestinian President Mahmoud Abbas indicated a possible softening of his position in a Tuesday night address to prominent American Jewish figures.

The Palestinian ambassador to the United Nations later said Abbas’ comments had been misconstrued and Abbas was still ready to walk away.

In Israel the story led news reports before being overtaken by the outburst of violence.

Clashes erupted in the Silwan neighborhood shortly after a 32-year-old Palestinian man was killed by a private Israeli security guard watching over Jewish families in the area. About 70 ultranationalist Jewish families live in Silwan, amid some 50,000 Palestinian residents.

Israeli police said the man, Samir Sirhan, had a criminal record and was shot overnight after a group of youths pelted the guard with stones. But residents said that Sirhan, a father of five young children, was unlikely to have participated in the violence. They also noted he was killed at about 4 a.m., an unlikely time for stone throwing.

After the shooting, rioting spread throughout Silwan and to the nearby walled Old City. Police responded by firing tear gas.

Palestinian youths overturned three cars with passengers inside, in one case dragging a man out of his vehicle and stabbing him. They also smashed the windows of five buses.

Ten Israelis were wounded, including the stabbing victim who was seriously hurt, police said. Palestinian medics said 14 people were slightly injured.