United Nations officials said Tuesday that as many as 10,000 residents of a Palestinian refugee neighborhood in the Syrian port city of Latakia had fled during a four-day assault, as security forces carried out more arrests and intimidation in what residents said was a government attempt to rebuild a wall of fear in one of Syria’s largest cities.

Latakia, on the country’s Mediterranean coast, is the third locale to bear the full brunt of military and security forces this month, though the government has also persisted in its crackdown on the suburbs of Damascus and Homs, the third-largest city. The violence has provoked international condemnations that have grown sharper, but still stopped short of demanding that President Bashar al-Assad step down.

On Tuesday in Washington, Secretary of State Hillary Rodham Clinton said it was more effective to forge international consensus against Mr. Assad — as well as intensify economic pressure through sanctions — than for the United States alone to lead the way.

“It’s not going to be any news if the United States says Assad needs to go,” Mrs. Clinton said at the National Defense University. “O.K., fine, what’s next? If Turkey says it, if King Abdullah says it, if other people say it, there is no way the Assad regime can ignore it.”

The United Nations Relief and Works Agency, which assists Palestinian refugees, said that it had no information on the whereabouts of the Latakia Palestinians. Activists have said many of the displaced have left for the countryside or Aleppo, Syrian’s second-largest city, to the northeast.

“A forgotten population has now become a disappeared population,” said Christopher Gunness, spokesman for the agency in Jerusalem, calling the situation “very, very worrying.”

The refugee neighborhood, Raml, was set up after 1948, when Palestinians fled or were expelled from their homes during the fighting at the creation of Israel. It grew into one of the city’s largest neighborhoods, drawing poor job-seekers, but it still lacks some basic services. Demonstrations have erupted there and nearby since the country’s uprising began in March, and activists there insisted that the crackdown would fail to quell the spirit of dissent.

“The residents in Raml will rally the same day the army pulls out,” said one, Ahmed Bogdash. “They are poor and they have nothing to lose.”

Mr. Gunness said forces had directed heavy fire into the neighborhood and that Syrian security officials had told some of the residents to leave, suggesting an impending military operation. By Tuesday, Raml was “all but deserted,” he added, citing latest reports from what he described as a broad range of reliable sources. The Syrian authorities have so far refused the refugee agency access to Raml, he said, leading to fears that some wounded or elderly residents could be stranded.

The reports from Latakia made headlines in Palestinian newspapers in the West Bank on Tuesday and prompted a strong response from Palestinian officials, though there was no evidence that the Raml neighborhood itself was a specific target of the crackdown.

“We urge the Syrian authorities to stop the attack on the refugee camp immediately,” said Nabil Abu Rudeineh, a spokesman for the Palestinian president, Mahmoud Abbas. “It is unacceptable, we cannot accept it,” he said.

Another senior Palestinian official, Yasser Abed Rabbo, has described the attack on Raml as “a crime against humanity.” Speaking on the official Voice of Palestine Radio on Tuesday, Mr. Abed Rabbo said that the Syrian government had “lost rationality.”

Syria has long given residence to Palestinian factions opposed to Mr. Abbas, including Hamas and some splinter Palestinian groups, and many Palestinians recall Syria’s decision to intervene decisively against them in 1976 during the Lebanese civil war. So far, Hamas has sought to avoid alienating the government in Damascus while stopping short of statements of support, like those from Hezbollah, the Lebanese Shiite Muslim movement and, even more pronounced, the allied Amal movement in Lebanon. In a pro-Hamas newspaper in Gaza, a columnist criticized the ferocity of the Syrian crackdown.

Gunfire was still heard Tuesday, though it seemed less intense. “It’s collective punishment against the people of Latakia,” Mr. Bogdash said.