NEW YORK (CNN) -- The violence in the Middle East prompted supporters of both sides to take to the streets Friday in several cities across the United States.
Roughly 15,000 pro-Palestinian protesters took to the streets of New York City, blasting Israeli military strikes against Palestinian targets, faulting the United States for its support of Israel and calling for peace in the Middle East.
Smaller crowds of Palestinian supporters gathered in Philadelphia, Cleveland, Atlanta and Washington. Near the White House, Arab-American demonstrators were outnumbered by about 1,000 Jewish-American protesters.
The New York protesters, under heavy police escort, began marching shortly after 12:30 p.m. in midtown Manhattan and headed toward a plaza across from the United Nations where they planned to hold a prayer service.
The mood of the crowd varied. Many expressed anger at Israel, and some
young men stomped on an Israeli flag. They compared Israel's treatment of Palestinians to a holocaust. One sign compared the Star of David to a swastika.
Other demonstrators focused on the United States, saying Washington has
been too pro-Israeli over the years and needed to take a harder line against
its ally.
Ahmed Alkhatib, president of the National Muslim Merchants Association,
said thousands of Palestinian-Americans were watching how U.S. leaders
responded to the Middle East crisis.
"We will remember in November," he said.
Competing demonstrations in D.C.
In Washington, more than 1,000 Jewish-Americans and several hundred Arab-Americans held competing demonstrations within a few hundred yards of each other in Lafayette Park, just across from the White House.
A heavy police presence kept the two groups apart, but occasionally there
were confrontations.
With television cameras rolling, two men argued until the pro-Palestinian demonstrator shooed his rival away.
"We don't want to talk to you. Just go, go," he said.
Chicago mayor appeals for dialogue
Hundreds of pro-Palestinian demonstrators marched in downtown Chicago on Friday.
The protest came one day after several attacks against Jews in the city.
A Jewish rabbi narrowly escaped injury Thursday when his car was sprayed by bullets in a drive-by shooting.
In the two other incidents a few blocks apart, people in a van slung marbles by slingshot at two men, one of whom was asked, "Hey, are you Jewish?" Neither victim was hit and three teen-agers were being questioned, a police spokeswoman said.
Police would not speculate on whether the incidents were related to heightened tensions in the Middle East.
The director of a local Jewish organization said the attacks were clearly connected to events overseas.
"Once again, when things flare up there, Arabs and Muslims act in solidarity with their brethren with illegal acts here," said Jay Tcath, director of the Jewish Community Relations Council.
But Arab-American leaders condemned the incidents and staged protests and a strike of their own.
"We don't condone those attacks at all. We are not encouraging any incidents like that," said Ray Hanania, the publisher of an Arab-American newspaper. "We're doing all we can to quell emotions, to try to direct them into productive protest."
Some of the protests in Chicago were aimed at U.S. media outlets that Arab-American groups feel are biased against the Palestinians.
Chicago Mayor Richard Daley appealed for dialogue and police superintendent Terry Hillard said more officers would be assigned in the northwest side community where the attacks occurred.
N.Y. police on 'Bravo' alert
A New York police spokesman also said its force had been put on "Bravo" status, meaning that security would be tighter at all police and government buildings, as well as at some landmarks, tourist attractions and religious buildings and any location associated with the Israeli government or the Palestinian Authority.
That includes the Israeli consulate in midtown Manhattan, which was the site of rallies and demonstrations, both for and against Israel over the past few days.
In an unusual move, mosques in the New York area were closed Friday so that Muslims from around the region could attend the rally at the United Nations, the New York Times reported.
Mosques, where the most devout Muslims gather five times a day to pray, rarely close.
Reuters contributed to this report.